ELF Library Functions                          elfgetident(3ELF)



NAME
     elfgetident, elfgetphnum, elfgetshnum, elfgetshstrndx  -
     retrieve ELF header data

SYNOPSIS
     cc [ flag ... ] file ... -lelf [ library ... ]
     #include 

     char * elfgetident(Elf *elf, sizet *dst);


     int elfgetphnum(Elf *elf, sizet *dst);


     int elfgetshnum(Elf *elf, sizet *dst);


     int elfgetshstrndx(Elf *elf, sizet *dst);


DESCRIPTION
     As elf(3ELF) explains, ELF provides a framework for  various
     classes  of  files,  where basic objects might have 32 or 64
     bits. To accommodate these differences, without forcing  the
     larger  sizes  on  smaller machines, the initial bytes in an
     ELF file hold identification information common to all  file
     classes. The eident of every ELF header has EINIDENT bytes
     with interpretations described in the following table.



     eident Index        Value                 Purpose

     EIMAG0              ELFMAG0               File identification
     EIMAG1              ELFMAG1
     EIMAG2              ELFMAG2
     EIMAG3              ELFMAG3

     EICLAS             ELFCLASNONE          File class
                          ELFCLAS32
                          ELFCLAS64

     EIDATA              ELFDATANONE           Data encoding
                          ELFDATA2LSB
                          ELFDATA2MSB

     EIVERSION           EVCURENT            File version

     7-15                 0                     Unused, set to zero






SunOS 5.11          Last change: 15 Nov 2005                    1






ELF Library Functions                          elfgetident(3ELF)



     Other kinds of files might have identification data,  though
     they  would  not  conform to eident. See elfkind(3ELF) for
     information on other kinds of files.


     The elfgetident() function returns a pointer to the initial
     bytes  of  the  file.  If the library recognizes the file, a
     conversion from the file  image  to  the  memory  image  can
     occur. The identification bytes are guaranteed to be unmodi-
     fied, though the size of the unmodified area depends on  the
     file  type.  If  the  dst  argument is non-null, the library
     stores the number of identification bytes in the location to
     which dst points. If no data are present, elf is NUL, or an
     error occurs, the return value is a  null  pointer,  with  0
     stored through dst, if dst is non-null.


     The elfgetphnum() function obtains the  number  of  program
     headers  recorded in the ELF file. The number of sections in
     a file is typically recorded in the ephnum field of the ELF
     header. A file that requires the ELF extended program header
     records the value PNXNUM in the ephnum field  and  records
     the  number  of  sections  in  the  shinfo field of section
     header 0. See USAGE. The dst argument points to the location
     where the number of sections is stored. If elf is NUL or an
     error occurs, elfgetphnum() returns 0.


     The elfgetshnum() function obtains the number  of  sections
     recorded  in  the ELF file. The number of sections in a file
     is typically recorded  in  the  eshnum  field  of  the  ELF
     header.  A  file  that requires ELF extended section records
     the value 0 in the eshnum field and records the  number  of
     sections  in  the  shsize  field  of  section header 0. See
     USAGE. The dst argument points to  the  location  where  the
     number  of sections is stored. If a call to elfnewscn(3ELF)
     that uses the same elf descriptor is  performed,  the  value
     obtained  by elfgetshnum() is valid only after a successful
     call to elfupdate(3ELF). If elf is NUL or an error occurs,
     elfgetshnum() returns 0.


     The elfgetshstrndx() function obtains the section index  of
     the  string table associated with the section headers in the
     ELF file. The section header string table index is typically
     recorded  in  the eshstrndx field of the ELF header. A file
     that  requires  ELF  extended  section  records  the   value
     SHNXINDEX  in  the  eshstrndx field and records the string
     table index in the shlink field of section  header  0.  See
     USAGE.  The  dst  argument  points to the location where the
     section header string table index is stored. If elf is  NUL
     or an error occurs, elfgetshstrndx() returns 0.



SunOS 5.11          Last change: 15 Nov 2005                    2






ELF Library Functions                          elfgetident(3ELF)



USAGE
     ELF extended sections allow an ELF file to contain more than
     0xff00 (SHNLORESERVE) section. ELF extended program headers
     allow an ELF file to contain 0xffff (PNXNUM) or  more  pro-
     gram  headers.  See  the Linker and Libraries Guide for more
     information.

RETURN VALUES
     Upon successful completion, elfgetident(),  elfgetphnum(),
     elfgetshnum(),  and  elfgetshstrndx()  functions return 1.
     Otherwise, they return 0.

ATRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Interface Stability          Stable                      
    
     MT-Level                     MT-Safe                     
    


SEE ALSO
     elf(3ELF),       elf32getehdr(3ELF),       elfbegin(3ELF),
     elfkind(3ELF),     elfnewscn(3ELF),     elfrawfile(3ELF),
     elfupdate(3ELF), libelf(3LIB), attributes(5)


     Linker and Libraries Guide





















SunOS 5.11          Last change: 15 Nov 2005                    3