User Commands pax(1)
NAME
pax - portable archive interchange
SYNOPSIS
pax [-cdnv] [-H -L] [-f archive] [-o options]...
[-s replstr]... [pattern]...
pax -r [-cdiknuv@/] [-H -L] [-f archive] [-o options]...
[-p string]... [-s replstr]... [pattern]...
pax -w [-dituvX@/] [-H -L] [-b blocksize] [-a]
[-f archive] [-o options]... [-s replstr]...
[-x format] [file]...
pax -r -w [-diklntuvX@/] [-H -L] [-o options]...
[-p string]... [-s replstr]... [file]... directory
DESCRIPTION
pax reads, writes, and writes lists of the members of
archive files and copies directory hierarchies. A variety of
archive formats are supported. See the -x format option.
Modes of Operations
The action to be taken depends on the presence of the -r and
-w options. The four combinations of -r and -w are referred
to as the four modes of operation: list, read, write, and
copy modes, corresponding respectively to the four forms
shown in the SYNOPSIS.
list In list mode, that is, when neither -r nor -w are
specified, pax writes the names of the members of
the archive file read from the standard input, with
path names matching the specified patterns, to
standard output. If a named file has extended
attributes, the extended attributes are also
listed. If a named file is of type directory, the
file hierarchy rooted at that file is listed as
well.
read In read mode, that is, when -r is specified, but -w
is not, pax extracts the members of the archive
file read from the standard input, with path names
matching the specified patterns. If an extracted
file is of type directory, the file hierarchy
rooted at that file is extracted as well. The
extracted files are created performing path name
resolution with the directory in which pax was
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User Commands pax(1)
invoked as the current working directory.
If an attempt is made to extract a directory when
the directory already exists, this is not con-
sidered an error. If an attempt is made to extract
a FIFO when the FIFO already exists, this is not
considered an error.
The ownership, access and modification times, and
file mode of the restored files are discussed under
the -p option.
write In write mode, that is, when -w is specified, but
-r is not, pax writes the contents of the file
operands to the standard output in an archive for-
mat. If no file operands are specified, a list of
files to copy, one per line, are read from the
standard input. A file of type directory includes
all of the files in the file hierarchy rooted at
the file.
copy In copy mode, that is, when both -r and -w are
specified, pax copies the file operands to the des-
tination directory.
If no file operands are specified, a list of files
to copy, one per line, are read from the standard
input. A file of type directory includes all of the
files in the file hierarchy rooted at the file.
The effect of the copy is as if the copied files
were written to an archive file and then subse-
quently extracted, except that there can be hard
links between the original and the copied files. If
the destination directory is a subdirectory of one
of the files to be copied, the results are unspeci-
fied. It is an error if directory does not exist,
is not writable by the user, or is not a directory.
In read or copy modes, if intermediate directories are
necessary to extract an archive member, pax performs actions
equivalent to the mkdir(2) function, called with the follow-
ing arguments:
o The intermediate directory used as the path argu-
ment.
o The octal value of 777 or rwx (read, write, and
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execute permissions) as the mode argument (see
chmod(1)).
If any specified pattern or file operands are not matched by
at least one file or archive member, pax writes a diagnostic
message to standard error for each one that did not match
and exits with a non-zero exit status.
The supported archive formats are automatically detected on
input. The default output archive format is tar(1).
A single archive can span multiple files. pax determines
what file to read or write as the next file.
If the selected archive format supports the specification of
linked files, it is an error if these files cannot be linked
when the archive is extracted, except if the files to be
linked are symbolic links and the system is not capable of
making hard links to symbolic links. In that case, separate
copies of the symbolic link are created instead. Any of the
various names in the archive that represent a file can be
used to select the file for extraction. For archive formats
that do not store file contents with each name that causes a
hard link, if the file that contains the data is not
extracted during this pax session, either the data is
restored from the original file, or a diagnostic message is
displayed with the name of a file that can be used to
extract the data. In traversing directories, pax detects
infinite loops, that is, entering a previously visited
directory that is an ancestor of the last file visited. When
it detects an infinite loop, pax writes a diagnostic message
to standard error and terminates.
OPTIONS
The following options are supported:
-a Appends files to the end of the archive.
This option does not work for some archive
devices, such as 1/4-inch streaming tapes
and 8mm tapes.
-b blocksize Blocks the output at a positive decimal
integer number of bytes per write to the
archive file. Devices and archive formats
can impose restrictions on blocking. Block-
ing is automatically determined on input.
Portable applications must not specify a
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blocksize value larger than 32256. Default
blocking when creating archives depends on
the archive format. See the -x option below.
-c Matches all file or archive members except
those specified by the pattern or file
operands.
-d Causes files of type directory being copied
or archived or archive members of type
directory being extracted or listed to match
only the file or archive member itself and
not the file hierarchy rooted at the file.
-f archive Specifies the path name of the input or out-
put archive, overriding the default standard
input (in list or read modes) or standard
output (write mode).
-H If a symbolic link referencing a file of
type directory is specified on the command
line, pax archives the file hierarchy rooted
in the file referenced by the link, using
the name of the link as the root of the file
hierarchy. Otherwise, if a symbolic link
referencing a file of any other file type
which pax can normally archive is specified
on the command line, then pax archives the
file referenced by the link, using the name
of the link. The default behavior is to
archive the symbolic link itself.
-i Interactively renames files or archive
members. For each archive member matching a
pattern operand or file matching a file
operand, a prompt is written to the file
/dev/tty. The prompt contains the name of
the file or archive member. A line is then
read from /dev/tty. If this line is blank,
the file or archive member is skipped. If
this line consists of a single period, the
file or archive member is processed with no
modification to its name. Otherwise, its
name is replaced with the contents of the
line. pax immediately exits with a non-zero
exit status if end-of-file is encountered
when reading a response or if /dev/tty
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cannot be opened for reading and writing.
The results of extracting a hard link to a
file that has been renamed during extraction
are unspecified.
-k Prevents the overwriting of existing files.
-l Links files. In copy mode, hard links are
made between the source and destination file
hierarchies whenever possible. If specified
in conjunction with -H or -L, when a sym-
bolic link is encountered, the hard link
created in the destination file hierarchy is
to the file referenced by the symbolic link.
If specified when neither -H nor -L is
specified, when a symbolic link is encoun-
tered, the implementation creates a hard
link to the symbolic link in the source file
hierarchy or copies the symbolic link to the
destination.
-L If a symbolic link referencing a file of
type directory is specified on the command
line or encountered during the traversal of
a file hierarchy, pax archives the file
hierarchy rooted in the file referenced by
the link, using the name of the link as the
root of the file hierarchy. Otherwise, if a
symbolic link referencing a file of any
other file type which pax can normally
archive is specified on the command line or
encountered during the traversal of a file
hierarchy, pax archives the file referenced
by the link, using the name of the link. The
default behavior is to archive the symbolic
link itself.
-n Selects the first archive member that
matches each pattern operand. No more than
one archive member is matched for each pat-
tern, although members of type directory
still match the file hierarchy rooted at
that file.
-o options Provides information to the implementation
to modify the algorithm for extracting or
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writing files. The value of options consists
of one or more comma-separated keywords of
the form:
keyword[:]=value][,keyword[:]=value], ...]
Some keywords apply only to certain file
formats, as indicated with each description.
Use of keywords that are inapplicable to the
file format being processed produces unde-
fined results.
Keywords in the options argument must be a
string that would be a valid portable
filename.
Keywords are not expected to be filenames,
merely to follow the same character composi-
tion rules as portable filenames.
Keywords can be preceded with white space.
The value field consists of zero or more
characters. Within value, the application
precedes any literal comma with a backslash,
which is ignored, but preserves the comma as
part of value. A comma as the final charac-
ter, or a comma followed solely by white
space as the final characters, in options is
ignored. Multiple -o options can be speci-
fied. If keywords given to these multiple -o
options conflict, the keywords and values
appearing later in command line sequence
take precedence and the earlier ones are
silently ignored. The following keyword
values of options are supported for the file
formats as indicated:
delete=pattern
This keyword is applicable only to the
-x pax format. When used in write or
copy mode, pax omits from extended
header records that it produces any key-
words matching the string pattern. When
used in read or list mode, pax ignores
any keywords matching the string pattern
in the extended header records. In both
cases, matching is performed using the
pattern matching notation. For example:
-o delete=security.*
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would suppress security-related informa-
tion.
When multiple -o delete=pattern options
are specified, the patterns are addi-
tive. All keywords matching the speci-
fied string patterns are omitted from
extended header records that pax pro-
duces.
exthdr.name=string
This keyword is applicable only to the
-x pax format. This keyword allows user
control over the name that is written
into the ustar header blocks for the
extended header. The name is the con-
tents of string, after the following
character substitutions have been made:
%d The directory name of the file,
equivalent to the result of the
dirname utility on the translated
path name.
%f The filename of the file,
equivalent to the result of the
basename utility on the translated
path name.
%p The process ID of the pax process.
%% A '%' character.
Any other '%' characters in string pro-
duce undefined results.
If no -o exthdr.name=string is speci-
fied, pax uses the following default
value:
%d/PaxHeaders.%p/%f
globexthdr.name=string
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This keyword is applicable only to the
-x pax format. When used in write or
copy mode with the appropriate options,
pax creates global extended header
records with ustar header blocks that
are treated as regular files by previous
versions of pax. This keyword allows
user control over the name that is writ-
ten into the ustar header blocks for
global extended header records. The name
is the contents of string, after the
following character substitutions have
been made:
%n An integer that represents the
sequence number of the global
extended header record in the
archive, starting at 1.
%p The process ID of the pax process.
%% A '%' character.
Any other '%' characters in string pro-
duce undefined results.
If no -o globexthdr.name=string is
specified, pax uses the following
default value:
$TMPDIR/GlobalHead.%p.%n
where $TMPDIR represents the value of
the TMPDIR environment variable. If
TMPDIR is not set, pax uses /tmp.
invalid=action
This keyword is applicable only to the
-x pax format. This keyword allows user
control over the action pax takes upon
encountering values in an extended
header record that, in read or copy
mode, are invalid in the destination
hierarchy or, in list mode , cannot be
written in the codeset and current
locale of the implementation. The fol-
lowing are invalid values that are
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recognized by pax:
o In read or copy mode, a
filename or link name that con-
tains character encodings
invalid in the destination
hierarchy. For example, the
name can contain embedded NULs.
o In read or copy mode, a
filename or link name that is
longer than the maximum allowed
in the destination hierarchy,
for either a path name com-
ponent or the entire path name.
o In list mode, any character
string value (filename, link
name, user name, and so on)
that cannot be written in the
codeset and current locale of
the implementation.
The following mutually-exclusive values
of the action argument are supported:
bypass In read or copy mode, pax
bypasses the file, causing no
change to the destination
hierarchy. In list mode, pax
writes all requested valid
values for the file, but its
method for writing invalid
values is unspecified.
rename In read or copy mode, pax acts
as if the -i option were in
effect for each file with
invalid filename or link name
values, allowing the user to
provide a replacement name
interactively. In list mode,
pax behaves identically to the
bypass action.
UTF-8 pax uses the actual UTF-8
encoding for the name when it
is used in read, copy, or list
mode and a filename, link
name, owner name, or any other
field in an extended header
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record cannot be translated
from the pax UTF-8 codeset
format to the codeset and
current locale of the imple-
mentation.
write In read or copy mode, pax
writes the file, translating
the name, regardless of
whether this can overwrite an
existing file with a valid
name. In list mode, pax
behaves identically to the
bypass action.
If no -o invalid= option is specified,
pax acts as if -o invalid=bypass were
specified. Any overwriting of existing
files that can be allowed by the -o
invalid= actions are subject to permis-
sion (-p) and modification time (-u)
restrictions, and are suppressed if the
-k option is also specified.
linkdata
This keyword is applicable only to the
-x pax format. In write mode, pax writes
the contents of a file to the archive
even when that file is merely a hard
link to a file whose contents have
already been written to the archive.
listopt=format
This keyword specifies the output format
of the table of contents produced when
the -v option is specified in list mode.
(See List Mode Format Specifications
below.) To avoid ambiguity, the
listopt=format is the only or final
keyword=value pair in an -o option-
argument. All characters in the
remainder of the option-argument are
considered to be part of the format
string. When multiple -o listopt=format
options are specified, the format
strings are considered to be a single,
concatenated string, evaluated in
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command line order.
times
This keyword is applicable only to the
-x pax and -x xustar formats. When used
in write or copy mode, pax includes
atime and mtime extended header records
for each file.
In addition to these keywords, if the -x pax
format is specified, any of the keywords and
values, including implementation extensions,
can be used in -o option-arguments, in
either of two modes:
keyword=value When used in write or copy
mode, these keyword/value
pairs are included at the
beginning of the archive
as typeflag g global
extended header records.
When used in read or list
mode, these keyword/value
pairs act as if they had
been at the beginning of
the archive as typeflag g
global extended header
records.
keyword:=value When used in write or copy
mode, these keyword/value
pairs are included as
records at the beginning
of a typeflag x extended
header for each file. This
is equivalent to the
equal-sign form except
that it creates no
typeflag g global extended
header records. When used
in read or list mode,
these keyword/value pairs
act as if they were
included as records at the
end of each extended
header. Thus, they over-
ride any global or file-
specific extended header
record keywords of the
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same names. For example,
in the command:
pax -r -o "
gname:=mygroup,
" %s", value of keyword, contents of link
Otherwise, the %L conversion specification is the
equivalent of %F.
OPERANDS
The following operands are supported:
directory The destination directory path name for copy
mode.
file A path name of a file to be copied or archived.
pattern A pattern matching one or more path names of
archive members. A pattern must conform to the
pattern matching notation found on the
fnmatch(5) manual page. The default, if no pat-
tern is specified, is to select all members in
the archive.
OUTPUT
Output formats are discussed below:
Standard Output
In write mode, if -f is not specified, the standard output
is the archive formatted according to one of the formats
described below. See -x format for a list of supported for-
mats.
In list mode, when the -o listopt=format option has been
specified, the selected archive members are written to stan-
dard output using the format described above under List Mode
Format Specifications. In list mode without the -o
listopt=format option, the table of contents of the selected
archive members are written to standard output using the
following format:
"%s\n", pathname
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If the -v option is specified in list mode, the table of
contents of the selected archive members are written to
standard output using the following formats:
o For path names representing hard links to previous
members of the archive:
"%s == %s\n",
where is the format specified by
the ls command with the -l option. When writing
path names in this format, it is unspecified what
is written for fields for which the underlying
archive format does not have the correct informa-
tion, although the correct number of blank-
character-separated fields is written.
In list mode, standard output is not buffered more than a
line at a time.
Standard Error
If -v is specified in read, write or copy modes, pax writes
the path names it processes to the standard error output
using the following format:
"%s\n", pathname
These path names are written as soon as processing is begun
on the file or archive member, and are flushed to standard
error. The trailing NEWLINE character, which is not buf-
fered, is written when the file has been read or written.
If the -s option is specified, and the replacement string
has a trailing p, substitutions are written to standard
error in the following format:
"%s >> %s\n", ,
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In all operating modes of pax, optional messages of unspeci-
fied format concerning the input archive format and volume
number, the number of files, blocks, volumes, and media
parts as well as other diagnostic messages can be written to
standard error.
In all formats, for both standard output and standard error,
it is unspecified how non-printable characters in path names
or link names are written.
When pax is in read mode or list mode, using the -x pax
archive format, and a file name, link name, owner name, or
any other field in an extended header record cannot be
translated from the pax UTF-8 codeset format to the codeset
and current locale of the implementation, pax writes a diag-
nostic message to standard error, processes the file as
described for the -o invalid=option, and then processes the
next file in the archive.
Output Files
In read mode, the extracted output files are of the archived
file type. In copy mode, the copied output files are the
type of the file being copied . In either mode, existing
files in the destination hierarchy are overwritten only when
all permission (-p), modification time (-u), and invalid-
value (-o invalid=) tests allow it. In write mode, the out-
put file named by the -f option-argument is a file formatted
according to one of the specifications in IE Std 1003.1-
2001.
ERORS
If pax cannot create a file or a link when reading an
archive, or cannot find a file when writing an archive, or
cannot preserve the user ID, group ID, or file mode when the
-p option is specified, a diagnostic message is written to
standard error and a non-zero exit status is returned, but
processing continues. In the case where pax cannot create a
link to a file, pax does not, by default, create a second
copy of the file.
If the extraction of a file from an archive is prematurely
terminated by a signal or error, pax can have only partially
extracted the file or, if the -n option was not specified,
can have extracted a file of the same name as that specified
by the user, but which is not the file the user wanted.
Additionally, the file modes of extracted directories can
have additional bits from the read, write, execute mask set
as well as incorrect modification and access times.
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USAGE
The -p (privileges) option was invented to reconcile differ-
ences between historical tar(1) and cpio(1) implementations.
In particular, the two utilities use -m in diametrically
opposed ways. The -p option also provides a consistent means
of extending the ways in which future file attributes can be
addressed, such as for enhanced security systems or high-
performance files. Although it can seem complex, there are
really two modes that are most commonly used:
-p e Preserve everything. This would be used by the his-
torical superuser, someone with all the appropriate
privileges, to preserve all aspects of the files as
they are recorded in the archive. The e flag is the
sum of o and p, and other implementation-dependent
attributes.
-p p Preserve the file mode bits. This would be used by
the user with regular privileges who wished to
preserve aspects of the file other than the owner-
ship. The file times are preserved by default, but
two other flags are offered to disable these and use
the time of extraction.
The one path name per line format of standard input pre-
cludes path names containing newlines. Although such path
names violate the portable filename guidelines, they can
exist and their presence can inhibit usage of pax within
shell scripts. This problem is inherited from historical
archive programs. The problem can be avoided by listing file
name arguments on the command line instead of on standard
input.
It is almost certain that appropriate privileges are
required for pax to accomplish parts of this. Specifically,
creating files of type block special or character special,
restoring file access times unless the files are owned by
the user (the -t option), or preserving file owner, group,
and mode (the -p option) all probably require appropriate
privileges.
In read mode, implementations are permitted to overwrite
files when the archive has multiple members with the same
name. This can fail if permissions on the first version of
the file do not permit it to be overwritten.
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When using the -x xustar and -x -pax archive formats, if the
underlying file system reports that the file being archived
contains holes, the Solaris pax utility records the presence
of holes in an extended header record when the file is
archived. If this extended header record is associated with
a file in the archive, those holes are recreated whenever
that file is extracted from the archive. See the SEKDATA
and SEKHOLE whence values in lseek(2). In all other cases,
any NUL (\0) characters found in the archive is written to
the file when it is extracted.
See largefile(5) for the description of the behavior of pax
when encountering files greater than or equal to 2 Gbyte (
2^31 bytes).
Standard Input
In write mode, the standard input is used only if no file
operands are specified. It is a text file containing a list
of path names, one per line, without leading or trailing
blanks. In list and read modes, if -f is not specified, the
standard input is an archive file. Otherwise, the standard
input is not used.
Input Files
The input file named by the archive option-argument, or
standard input when the archive is read from there, is a
file formatted according to one of the formats described
below. See Extended Description. The file /dev/tty is used
to write prompts and read responses.
EXAMPLES
Example 1 Copying the Contents of the Current Directory
The following command:
example% pax -w -f /dev/rmt/1m .
copies the contents of the current directory to tape drive
1, medium density. This assumes historical System V device
naming procedures. The historical BSD device name would be
/dev/rmt9.
Example 2 Copying the Directory Hierarchy
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The following commands:
example% mkdir newdir
example% pax -rw olddir newdir
copy the olddir directory hierarchy to newdir.
Example 3 Reading an Archive Extracted Relative to the
Current Directory
The following command:
example% pax -r -s ',^/*usr/*,,' -f a.pax
reads the archive a.pax, with all files rooted in /usr in
the archive extracted relative to the current directory.
Example 4 Overriding the Default Output Description
Using the option:
-o listopt="%M %(atime)T %(size)D %(name)s"
overrides the default output description in Standard Output
and instead writes:
-rw-rw- - - Jan 12 15:53 2003 1492 /usr/foo/bar
Using the options:
-o listopt='%L\t%(size)D\n%.7' \
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-o listopt='(name)s\n%(atime)T\n%T'
overrides the default output description in standard output
and instead writes:
usr/foo/bar -> /tmp 1492
/usr/foo
Jan 12 15:53 1991
Jan 31 15:53 2003
ENVIRONMENT VARIABLES
See environ(5) for descriptions of the following environment
variables that affect the execution of pax: LANG, LCAL,
LCTYPE, LCMESAGES, LCTIME, and NLSPATH.
LCOLATE Determine the locale for the behaviour of
ranges, equivalence classes, and multi-
character collating elements used in the pat-
tern matching expressions for the pattern
operand, the basic regular expression for the
-s option, and the extended regular expression
defined for the yesexpr locale keyword in the
LCMESAGES category.
TMPDIR Determine the path name that provides part of
the default global extended header record
file, as described for the -o globexthdr= key-
word as described in the OPTIONS section.
TZ Determine the timezone used to calculate date
and time strings when the -v option is speci-
fied. If TZ is unset or null, an unspecified
default timezone is used.
EXIT STATUS
The following exit values are returned:
0 All files were processed successfully.
>0 An error occurred.
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EXTENDED DESCRIPTION
pax Interchange Format
A pax archive tape or file produced in the -xpax format con-
tains a series of blocks. The physical layout of the archive
is identical to the ustar format described in ustar Inter-
change Format. Each file archived is represented by the fol-
lowing sequence:
o An optional header block with extended header
records. This header block is of the form 27403
with a typeflag value of x or g. The extended
header records is included as the data for this
header block.
o A header block that describes the file. Any fields
in the preceding optional extended header overrides
the associated fields in this header block for this
file.
o Zero or more blocks that contain the contents of
the file.
At the end of the archive file there are two 512-byte blocks
filled with binary zeroes, interpreted as an end-of-archive
indicator.
The following is a schematic of an example archive with glo-
bal extended header records and two actual files in pax for-
mat archive. In the example, the second file in the archive
has no extended header preceding it, presumably because it
has no need for extended attributes.
Description Block
Global Extended Header ustar Header [typeflag=g]
Global Extended Header Data
File 1: Extended Header is included ustar Header [typeflag=x]
Extended Header Data
[typeflag=0]
ustar Header Data for File 1
File 2: No Extended Header is included ustar Header [typeflag=0]
Data for File2
End of Archive Indicator Block of binary zeros
Block of binary zeros
pax Header Block
The pax header block is identical to the ustar header block
described in ustar Interchange Format except that two
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User Commands pax(1)
additional typeflag values are defined:
g Represents global extended header records for the fol-
lowing files in the archive. The format of these
extended header records are as described in pax
Extended Header. Each value affects all subsequent
files that do not override that value in their own
extended header record and until another global
extended header record is reached that provides another
value for the same field. The typeflag g global headers
should not be used with interchange media that could
suffer partial data loss in transporting the archive.
x Represents extended header records for the following
file in the archive (which has its own ustar header
block). The format of these extended header records is
as described in pax Extended Header.
For both of these types, the size field is the size of the
extended header records in octets. The other fields in the
header block are not meaningful to this version of pax. How-
ever, if this archive is read by pax conforming to a previ-
ous version of ISO POSIX-2:1993 Standard, the header block
fields are used to create a regular file that contains the
extended header records as data. Therefore, header block
field values should be selected to provide reasonable file
access to this regular file.
A further difference from the ustar header block is that
data blocks for files of typeflag 1 (the digit one) (hard
link) might be included, which means that the size field can
be greater than zero. Archives created by pax -o linkdata
includes these data blocks with the hard links.
pax Extended Header
A pax extended header contains values that are inappropriate
for the ustar header block because of limitations in that
format: fields requiring a character encoding other than
that described in the ISO/IEC 646: 1991 standard, fields
representing file attributes not described in the ustar
header, and fields whose format or length do not fit the
requirements of the ustar header. The values in an extended
header add attributes to the specified file or files or
override values in the specified header blocks, as indicated
in the following list of keywords. See the description of
the typeflag g header block.
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An extended header consists of one or more records, each
constructed as follows:
"%d %s=%s\n", length, keyword, value
The extended header records are encoded according to the
ISO/IEC 10646-1: 2000 standard (UTF-8). length, BLANK,
equals sign (=), and NEWLINE are limited to the portable
character set, as encoded in UTF-8. keyword and value can be
any UTF-8 characters. length is the decimal length of the
extended header record in octets, including the trailing
NEWLINE.
keyword is one of the entries from the following list or a
keyword provided as an implementation extension. Keywords
consisting entirely of lowercase letters, digits, and
periods are reserved for future standardization. A keyword
does not include an equals sign.
In the following list, the notation of file(s) or block(s)
are used to acknowledge that a keyword affects the specified
single file after a typeflag x extended header, but possibly
multiple files after typeflag g. Any requirements in the
list for pax to include a record when in write or copy mode
applies only when such a record has not already been pro-
vided through the use of the -o option. When used in copy
mode, pax behaves as if an archive had been created with
applicable extended header records and then extracted.
atime The file access time for the specified
files, equivalent to the value of the
statime member of the stat structure for a
file, as described by the stat(2) function.
The access time (atime) is restored if the
process has the appropriate privilege
required to do so. The format of the value
is as described in pax Extended Header File
Times.
charset The name of the character set used to encode
the data in the specified files. The entries
in the following table are defined to refer
to known standards; additional names can be
agreed on between the originator and reci-
pient.
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User Commands pax(1)
value Formal Standard
ISO-IR 646 1990 ISO/IEC646:1990
ISO-IR 8859 1 1998 ISO/IEC8859-1:1998
ISO-IR 8859 2 1999 ISO/IEC 8859-2:1999
ISO-IR 8859 3 1999 ISO/IEC 8859-3:1999
ISO-IR 8859 4 1999 ISO/IEC8859-4:1998
ISO-IR 8859 5 1999 ISO/IEC8859-5-1999
ISO-IR 8859 6 1999 ISO/IEC8859-6-1999
ISO-IR 8859 7 1987 ISO/IEC8859-7:1987
ISO-IR 8859 8 1999 ISO/IEC8859-8:1999
ISO-IR 8859 9 1999 ISO/IEC8859-9:1999
ISO-IR 8859 10 1998 ISO/IEC8859-10:1999
ISO-IR 8859 13 1998 ISO/IEC8859-13:1998
ISO-IR 8859 14 1998 ISO/IEC8859-14:1998
ISO-IR 8859 15 1999 ISO/IEC8859-15:1999
ISO-IR 10646 2000 ISO/IEC 10646:2000
ISO-IR 10646 2000 UTF-8 ISO/IEC 10646,UTF-8 encoding
BINARY None
The encoding is included in an extended
header for information only; when pax is
used as described in IE Std 1003.1-200x,
it does not translate the file data into any
other encoding. The BINARY entry indicates
unencoded binary data. When used in write or
copy mode, it is implementation-defined
whether pax includes a charset extended
header record for a file.
comment A series of characters used as a comment.
All characters in the value field are
ignored by pax.
gid The group ID of the group that owns the
file, expressed as a decimal number using
digits from the ISO/IEC 646: 1991 standard.
This record overrides the gid field in the
specified header blocks. When used in write
or copy mode, pax includes a gid extended
header record for each file whose group ID
is greater than 2097151 (octal 7777777).
gname The group of the files, formatted as a group
name in the group database. This record
overrides the gid and gname fields in the
specified header blocks, and any gid
extended header record. When used in read,
copy, or list mode, pax translates the name
from the UTF-8 encoding in the header record
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User Commands pax(1)
to the character set appropriate for the
group database on the receiving system. If
any of the UTF-8 characters cannot be
translated, and if the -o invalid=UTF-8
option is not specified, the results are
implementation-defined. When used in write
or copy mode, pax includes a gname extended
header record for each file whose group name
cannot be represented entirely with the
letters and digits of the portable character
set.
linkpath The pathname of a link being created to
another file, of any type, previously
archived. This record overrides the linkname
field in the specified ustar header blocks.
The specified ustar header block determines
the type of link created. If typeflag of the
specified header block is 1, it is a hard
link. If typeflag is 2, it is a symbolic
link and the linkpath value is the contents
of the symbolic link. pax translates the
name of the link (contents of the symbolic
link) from the UTF-8 encoding to the charac-
ter set appropriate for the local file sys-
tem. When used in write or copy mode, pax
includes a linkpath extended header record
for each link whose pathname cannot be
represented entirely with the members of the
portable character set other than NUL.
mtime The pathname of a link being created to
another file, of any type, previously
archived. This record overrides the linkname
field in the specified ustar header blocks.
The specified ustar header block determines
the type of link created. If typeflag of the
specified header block is 1, it is a hard
link. If typeflag is 2, it is a symbolic
link and the linkpath value is the contents
of the symbolic link. pax translates the
name of the link (contents of the symbolic
link) from the UTF-8 encoding to the charac-
ter set appropriate for the local file sys-
tem. When used in write or copy mode, pax
includes a linkpath extended header record
for each link whose pathname cannot be
represented entirely with the members of the
portable character set other than NUL.
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User Commands pax(1)
path The pathname of the specified files. This
record overrides the name and prefix fields
in the specified header blocks. pax
translates the pathname of the file from the
UTF-8 encoding to the character set
appropriate for the local file system. When
used in write or copy mode, pax includes a
path extended header record for each file
whose pathname cannot be represented
entirely with the members of the portable
character set other than NUL.
realtime.any The keywords prefixed by realtime are
reserved for future standardization.
security.any The keywords prefixed by security are
reserved for future standardization.
size The size of the file in octets, expressed as
a decimal number using digits from the
ISO/IEC 646: 1991 standard. This record
overrides the size field in the specified
header blocks. When used in write or copy
mode, pax includes a size extended header
record for each file with a size value
greater than 8589934591 (octal 77777777777).
uid The user ID of the file owner, expressed as
a decimal number using digits from the
ISO/IEC 646:1991 standard. This record over-
rides the uid field in the following header
block(s). When used in write or copy mode,
pax includes a uid extended header record
for each file whose owner ID is greater than
2097151 (octal 7777777).
uname The owner of the specified files, formatted
as a user name in the user database. This
record overrides the uid and uname fields in
the specified header blocks, and any uid
extended header record. When used in read,
copy, or list mode, pax translates the name
from the UTF-8 encoding in the header record
to the character set appropriate for the
user database on the receiving system. If
any of the UTF-8 characters cannot be
translated, and if the -o invalid= UTF-8
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User Commands pax(1)
option is not specified, the results are
implementation-defined. When used in write
or copy mode, pax includes a uname extended
header record for each file whose user name
cannot be represented entirely with the
letters and digits of the portable character
set.
If the value field is zero length, it deletes any header
block field, previously entered extended header value, or
global extended header value of the same name.
If a keyword in an extended header record (or in an -o
option-argument) overrides or deletes a corresponding field
in the ustar header block, pax ignores the contents of that
header block field.
Unlike the ustar header block fields, NULs does not delimit
values; all characters within the value field are considered
data for the field.
pax Extended Header Keyword Precedence
This section describes the precedence in which the various
header records and fields and command line options are
selected to apply to a file in the archive. When pax is used
in read or list modes, it determines a file attribute in the
following sequence:
1. If -o delete=keyword-prefix is used, the affected
attributes is determined from step 7, if applica-
ble, or ignored otherwise.
2. If -o keyword:= is used, the affected attributes is
ignored.
3. If -o keyword:=value is used, the affected attri-
bute is assigned the value.
4. If there is a typeflag x extended header record,
the affected attribute is assigned the value. When
extended header records conflict, the last one
given in the header takes precedence.
5. If -o keyword=value is used, the affected attribute
is assigned the value.
6. If there is a typeflag g global extended header
record, the affected attribute is assigned the
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User Commands pax(1)
value. When global extended header records con-
flict, the last one given in the global header
takes precedence.
7. Otherwise, the attribute is determined from the
ustar header block.
pax Extended Header File Times
pax writes an mtime record for each file in write or copy
modes if the file's modification time cannot be represented
exactly in the ustar header logical record described in
ustar Interchange Format. This can occur if the time is out
of ustar range, or if the file system of the underlying
implementation supports non-integer time granularities and
the time is not an integer. All of these time records are
formatted as a decimal representation of the time in seconds
since the Epoch. If a period (.) decimal point character is
present, the digits to the right of the point represents the
units of a sub-second timing granularity, where the first
digit is tenths of a second and each subsequent digit is a
tenth of the previous digit. In read or copy mode, pax trun-
cates the time of a file to the greatest value that is not
greater than the input header file time. In write or copy
mode, pax outputs a time exactly if it can be represented
exactly as a decimal number, and otherwise generates only
enough digits so that the same time is recovered if the file
is extracted on a system whose underlying implementation
supports the same time granularity.
ustar Interchange Format
A ustar archive tape or file contains a series of logical
records. Each logical record is a fixed-size logical record
of 512 octets. Although this format can be thought of as
being stored on 9-track industry-standard 12.7mm (0.5 in)
magnetic tape, other types of transportable media are not
excluded. Each file archived is represented by a header log-
ical record that describes the file, followed by zero or
more logical records that give the contents of the file. At
the end of the archive file there are two 512-octet logical
records filled with binary zeros, interpreted as an end-of-
archive indicator.
The logical records can be grouped for physical I/O opera-
tions, as described under the -bblocksize and -x ustar
options. Each group of logical records can be written with a
single operation equivalent to the write(2) function. On
magnetic tape, the result of this write is a single tape
physical block. The last physical block always is the full
size, so logical records after the two zero logical records
can contain undefined data.
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The header logical record is structured as shown in the fol-
lowing table. All lengths and offsets are in decimal.
Table 1 ustar Header Block
Field Name Octet Offset Length (in Octets)
name 0 100
mode 100 8
uid 108 8
gid 116 8
size 124 12
mtime 136 12
chksum 148 8
typeflag 156 1
linkname 157 100
magic 257 6
version 263 2
uname 265 32
gname 297 32
devmajor 329 8
devminor 337 8
prefix 345 155
All characters in the header logical record is represented
in the coded character set of the ISO/IEC 646: 1991 stan-
dard. For maximum portability between implementations, names
should be selected from characters represented by the port-
able filename character set as octets with the most signifi-
cant bit zero. If an implementation supports the use of
characters outside of slash and the portable filename char-
acter set in names for files, users, and groups, one or more
implementation-defined encodings of these characters are
provided for interchange purposes.
pax never creates filenames on the local system that cannot
be accessed using the procedures described in IE Std
1003.1-200x. If a filename is found on the medium that would
create an invalid filename, it is implementation-defined
whether the data from the file is stored on the file hierar-
chy and under what name it is stored. pax can choose to
ignore these files as long as it produces an error indicat-
ing that the file is being ignored. Each field within the
header logical record is contiguous; that is, there is no
padding used.
Each field within the header logical record is contiguous.
There is no padding used. Each character on the archive
medium is stored contiguously.
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The fields magic, uname and gname are character strings,
each of which is terminated by a NUL character. The fields
name, linkname, and prefix are NUL-terminated character
strings except when all characters in the array contain
non-NUL characters including the last character. The ver-
sion field is two octets containing the characters 00
(zero-zero) The typeflag contains a single character. All
other fields are leading zero-filled octal numbers using
digits from the ISO/IEC 646:1991 standard IRV. Each numeric
field is terminated by one or more SPACE of NUL characters.
Each character on the archive medium is stored contiguously.
The fields magic, uname, and gname are character strings
each terminated by a NUL character.
name, linkname, and prefix are NUL-terminated character
strings except when all characters in the array contain
non-NUL characters including the last character. The ver-
sion field is two octets containing the characters 00
(zero-zero). The typeflag contains a single character. All
other fields are leading zero-filled octal numbers using
digits from the ISO/IEC 646: 1991 standard IRV. Each numeric
field is terminated by one or more spaces or NUL charac-
ters.
The name and the prefix fields produce the pathname of the
file. A new pathname is formed, if prefix is not an empty
string (its first character is not NUL), by concatenating
prefix (up to the first NUL character), a slash character,
and name; otherwise, name is used alone. In either case,
name is terminated at the first NUL character. If prefix
begins with a NUL character, it is ignored. In this manner,
pathnames of at most 256 characters can be supported. If a
pathname does not fit in the space provided, pax notifies
the user of the error, and does not store any part of the
file-header or data-on the medium.
The linkname field does not use the prefix to produce a
pathname. As such, a linkname is limited to 100 characters.
If the name does not fit in the space provided, pax notifies
the user of the error, and does not attempt to store the
link on the medium. The mode field provides 12 bits encoded
in the ISO/IEC 646: 1991 standard octal digit representa-
tion. The encoded bits represent the following values in the
ustar mode field:
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User Commands pax(1)
Bit Value IE Std 1003.1-2001 Bit Description
04000 SISUID Set UID on execution
02000 SISGID Set GID on exectution
01000 reserved Reserved for future standardization
00400 SIRUSR Read permission for file owner class
00200 SIWUSR Write permission for file owner class
00100 SIXUSR Execute/search permission for file
owner class
00040 SIRGRP Read permission for file group class
00020 SIWGRP Write permission for file group class
00010 SIXGRP Execute/search permission for file
group class
00004 SIROTH Read permission for file other class
00002 SIWOTH Write permission for file other class
00001 SIXOTH Execute/search permission for file
other class
When appropriate privilege is required to set one of these
mode bits, and the user restoring the files from the archive
does not have the appropriate privilege, the mode bits for
which the user does not have appropriate privilege are
ignored. Some of the mode bits in the archive format are not
mentioned elsewhere in volume IE Std 1003.1-200x. If the
implementation does not support those bits, they can be
ignored.
The uid and gid fields are the user and group ID of the
owner and group of the file, respectively.
The size field is the size of the file in octets. If the
typeflag field is set to specify a file to be of type 1 (a
link) or 2 (a symbolic link), the size field is specified as
zero. If the typeflag field is set to specify a file of type
5 (directory), the size field is interpreted as described
under the definition of that record type. No data logical
records are stored for types 1, 2, or 5. If the typeflag
field is set to 3 (character special file), 4 (block special
file), or 6 (FIFO), the meaning of the size field is
unspecified by volume IE Std 1003.1-200x, and no data log-
ical records is stored on the medium. Additionally, for type
6, the size field is ignored when reading. If the typeflag
field is set to any other value, the number of logical
records written following the header is (size]511)/512,
ignoring any fraction in the result of the division.
The mtime field is the modification time of the file at the
time it was archived. It is the ISO/IEC 646: 1991 standard
SunOS 5.11 Last change: 16 Jul 2008 37
User Commands pax(1)
representation of the octal value of the modification time
obtained from the stat() function.
The chksum field is the ISO/IEC 646: 1991 standard IRV
representation of the octal value of the simple sum of all
octets in the header logical record. Each octet in the
header is treated as an unsigned value. These values are
added to an unsigned integer, initialized to zero, the pre-
cision of which is not less than 17 bits. When calculating
the checksum, the chksum field is treated as if it were all
spaces.
The typeflag field specifies the type of file archived. If a
particular implementation does not recognize the type, or
the user does not have appropriate privilege to create that
type, the file is extracted as if it were a regular file if
the file type is defined to have a meaning for the size
field that could cause data logical records to be written on
the medium. If conversion to a regular file occurs, pax pro-
duces an error indicating that the conversion took place.
All of the typeflag fields are coded in the ISO/IEC 646:
1991 standard IRV:
0 Represents a regular file. For backward
compatibility, a typeflag value of binary
zero ('\0') should be recognized as meaning
a regular file when extracting files from
the archive. Archives written with this
version of the archive file format create
regular files with a typeflag value of the
ISO/IEC 646: 1991 standard IRV '0'.
1 Represents a file linked to another file,
of any type, previously archived. Such
files are identified by each file having
the same device and file serial number. The
linked-to name is specified in the linkname
field with a NUL-character terminator if
it is less than 100 octets in length.
2 Represents a symbolic link. The contents of
the symbolic link are stored in the link-
name field.
3,4 Represents character special files and
block special files respectively. In this
case the devmajor and devminor fields
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User Commands pax(1)
contain information defining the device,
the format of which is unspecified by
volume IE Std 1003.1-200x. Implementa-
tions can map the device specifications to
their own local specification or can ignore
the entry.
5 Specifies a directory or subdirectory. On
systems where disk allocation is performed
on a directory basis, the size field con-
tain the maximum number of octets (which
can be rounded to the nearest disk block
allocation unit) that the directory can
hold. A size field of zero indicates no
such limiting. Systems that do not support
limiting in this manner should ignore the
size field.
6 Specifies a FIFO special file. The archiv-
ing of a FIFO file archives the existence
of this file and not its contents.
7 Reserved to represent a file to which an
implementation has associated some high-
performance attribute. Implementations
without such extensions should treat this
file as a regular file (type 0).
A-Z The letters A through Z inclusive are
reserved for custom implementations. All
other values are reserved for future ver-
sions of IE Std 1003.1-200x.
SUN.devmajor A Solaris extension to pax extended header
keywords. Specifies the major device number
of the file.
When used in write or copy mode and the
xustar or pax format (see -x format) was
specified, pax includes a SUN.devmajor
extended header record for each file whose
major device number is too large to fit in
8 octets.
SUN.devminor A Solaris extension to pax extended header
keywords. Specifies the minor device number
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User Commands pax(1)
of the file.
When used in write or copy mode and the
xustar or pax format (see -x format) is
specified, pax includes a SUN.devminor
extended header record for each file whose
minor device number is too large to fit in
8 octets.
SUN.holesdata A Solaris extension to pax extended header
keywords. Specifies the data and hole pairs
for a sparse file.
In write or copy modes and when the xustar
or pax format (see -x format) is specified,
pax includes a SUN.holesdate extended
header record if the underlying file system
supports the detection of files with holes
(see fpathconf(2)) and reports that there
is at least one hole in the file being
archived. value consists of two or more
consecutive entries of the following form:
SPACEdataoffsetSPACEholeoffset
where the data and hole offsets are the
long values returned by passing SEKDATA
and SEKHOLE to lseek(2), respectively.
For example, the following entry is an
example of the SUN.holesdata entry in the
extended header for a file with data
offsets at bytes 0, 24576, and 49152, and
hole offsets at bytes 8192, 32768, and
49159: 49 SUN.holesdata= 0 8192 24576 32768
49152 49159:
49 SUN.holesdata= 0 8192 24576 32768 49152 49159
When extracting a file from an archive in
read or copy modes, if a SUN.holesdata =
pair is found in the extended header for
the file, then the file is restored with
the holes identified using this data. For
example, for the SUN.holesdata provided in
the example above, bytes from 0 to 8192 are
restored as data, a hole is created up to
the next data position (24576), bytes 24576
to 32768 is restored as data, and so forth.
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User Commands pax(1)
X A Solaris custom typeflag implementation
which specifies an xustar format (see -x
format) extended header. The typeflag 'x'
extended header is treated as a ustar
typeflag 'x' extended header.
E A Solaris custom typeflag implementation
which specifies an extended attributes
header. See fsattr(5).
Attempts to archive a socket using ustar interchange format
produce a diagnostic message. Handling of other file types
is implementation-defined.
The magic field is the specification that this archive was
output in this archive format. If this field contains ustar
(the five characters from the ISO/IEC 646: 1991 standard IRV
shown followed by NUL), the uname and gname fields contain
the ISO/IEC 646: 1991 standard IRV representation of the
owner and group of the file, respectively (truncated to fit,
if necessary). When the file is restored by a privileged,
protection-preserving version of the utility, the user and
group databases are scanned for these names. If found, the
user and group IDs contained within these files are used
rather than the values contained within the uid and gid
fields.
cpio Interchange Format
The octet-oriented cpio archive format are a series of
entries, each comprising a header that describes the file,
name of the file, and contents of the file.
An archive can be recorded as a series of fixed-size blocks
of octets. This blocking is be used only to make physical
I/O more efficient. The last group of blocks are always at
the full size.
For the octet-oriented cpio archive format, the individual
entry information are in the order indicated and described
by the following table: Octet-Oriented cpio Archive Entry.
See the cpio.h header for additional details.
Header Field Name Length (in Octets) Interpreted as
cmagic 6 Octal number
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User Commands pax(1)
cdev 6 Octal number
cino 6 Octal number
cmode 6 Octal number
cuid 6 Octal number
cgid 6 Octal number
cnlink 6 Octal number
crdev 6 Octal number
cmtime 11 Octal number
cnamesize 6 Octal number
cfilesize 11 Octal number
Filename Field Name Length Interpreted as
cname cnamesize Pathname string
Filename Field Name Length Interpreted as
cfiledata cfilesize Data
cpio Header
For each file in the archive, a header as defined previously
written. The information in the header fields is written as
streams of the ISO/IEC 646: 1991 standard characters inter-
preted as octal numbers. The octal numbers are extended to
the necessary length by appending the ISO/IEC 646: 1991
standard IRV zeros at the most-significant-digit end of the
number. The result is written to the most-significant digit
of the stream of octets first. The fields are interpreted as
follows:
cmagic Identifies the archive as being a transport-
able archive by containing the identifying
value "070707".
cdev,cino Contains values that uniquely identify the
file within the archive (that is, no files
contain the same pair of cdev and cino
values unless they are links to the same
file). The values are determined in an
unspecified manner.
cmode Contains the file type and access permissions
as defined in the following table.
Directories, FIFOs, symbolic links, and
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User Commands pax(1)
regular files are supported on a system con-
forming to volume IE Std 1003.1-200x; addi-
tional values defined previously are reserved
for compatibility with existing systems.
Additional file types can be supported. Such
files should not be written to archives
intended to be transported to other systems.
File Permissions Name Value Indicates
CIRUSR 000400 by owner
CIWUSR 000200 by owner
CIXUSR 000100 by owner
CIRGRP 000040 by group
CWIWFGP 000020 by group
CWIXGRP 000010 by group
CWIROTH 000004 by others
CWIWOTH 000002 by others
CWIXOTH 000001 by others
CWISUID 004000 Set uid
WISGID 002000 Set gid
WISVTX 001000 Reserved
File Type Name Value Indicates
CISDIR 040000 Directory
CISFIFO 010000 FIFO
CISREG 0100000 Regular file
CISLNK 0120000 Symbolic link
CISBLK 060000 Block special file
CISCHR 020000 Character special file
CISOCK 0140000 Socket
CISCTG 0110000 Reserved
cuid Contains the user ID of the owner.
cgid Contains the group ID of the group
cnlink Contains a number greater than or equal to
the number of links in the archive referenc-
ing the file. If the -a option is used to
append to a cpio archive, pax does need not
to account for the files in the existing part
of the archive when calculating the cnlink
values for the appended part of the archive.
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User Commands pax(1)
It does also need not alter the cnlink
values in the existing part of the archive if
additional files with the same cdev and c-
ino values are appended to the archive.
crdev Contains implementation-defined information
for character or block special files.
cmtime Contains the latest time of modification of
the file at the time the archive was created.
cnamesize Contains the length of the pathname, includ-
ing the terminating NUL character.
cfilesize Contains the length of the file in octets.
This is the length of the data section fol-
lowing the header structure.
cpio Filename
The cname field contains the pathname of the file. The
length of this field in octets is the value of cnamesize.
If a filename is found on the medium that would create an
invalid pathname, it is implementation-defined whether the
data from the file is stored on the file hierarchy and under
what name it is stored. All characters are represented in
the ISO/IEC 646: 1991 standard IRV. For maximum portability
between implementations, names should be selected from char-
acters represented by the portable filename character set as
octets with the most significant bit zero. If an implementa-
tion supports the use of characters outside the portable
filename character set in names for files, users, and
groups, one or more implementation-defined encodings of
these characters are provided for interchange purposes.pax
does not create filenames on the local system that cannot be
accessed by way of the procedures described in volume IE
Std 1003.1-200x. If a filename is found on the medium that
would create an invalid filename, it is implementation-
defined whether the data from the file is stored on the
local file system and under what name it is stored. pax can
choose to ignore these files as long as it produces an error
indicating that the file is being ignored.
cpio File Data
Following cname, there is cfilesize octets of data.
Interpretation of such data occurs in a manner dependent on
the file. If cfilesize is zero, no data is contained in
cfiledata . When restoring from an archive:
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User Commands pax(1)
o If the user does not have the appropriate privilege
to create a file of the specified type, pax ignores
the entry and writes an error message to standard
error.
o Only regular files have data to be restored.
Presuming a regular file meets any selection cri-
teria that might be imposed on the format-reading
utility by the user, such data is restored.
o If a user does not have appropriate privilege to
set a particular mode flag, the flag is ignored.
Some of the mode flags in the archive format are
not mentioned in volume IE Std 1003.1-200x. If
the implementation does not support those flags,
they can be ignored.
cpio Special Entries
FIFO special files, directories, and the trailer are
recorded with cfilesize equal to zero. For other special
files, cfilesize is unspecified in volume IE Std 1003.1-
200x. The header for the next file entry in the archive are
written directly after the last octet of the file entry
preceding it. A header denoting the filename trailer indi-
cates the end of the archive; the contents of octets in the
last block of the archive following such a header are unde-
fined.
ATRIBUTES
See attributes(5) for descriptions of the following attri-
butes:
ATRIBUTE TYPE ATRIBUTE VALUE
Availability SUNWcsu
Interface Stability Committed
Standard See standards(5).
SEE ALSO
chmod(1), cpio(1), ed(1), printf(1), tar(1), mkdir(2),
lseek(2), stat(2), write(2), archives.h(3HEAD), attri-
butes(5), environ(5), fnmatch(5), formats(5)fsattr(5), lar-
gefile(5), regex(5), standards(5)
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User Commands pax(1)
IE Std 1003.1-200x, ISO/IEC 646: 1991, ISO POSIX-2:1993
Standard
SunOS 5.11 Last change: 16 Jul 2008 46
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