Standard C Library Functions                           fdopen(3C)



NAME
     fdopen - associate a stream with a file descriptor

SYNOPSIS
     #include 

     FILE *fdopen(int fildes, const char *mode);


DESCRIPTION
     The fdopen()  function  associates  a  stream  with  a  file
     descriptor fildes.


     The mode argument is a character string having  one  of  the
     following values:



     r or rb               Open a file for reading.
     w or wb               Open a file for writing.
     a or ab               Open a file for writing at end of file.
     r], rb] or r]b        Open a file  for  update  (reading  and
                           writing).
     w], wb] or w]b        Open a file  for  update  (reading  and
                           writing).
     a], ab] or a]b        Open a file  for  update  (reading  and
                           writing) at end of file.



     The meaning of these flags is exactly as specified  for  the
     fopen(3C)  function,  except  that modes beginning with w do
     not cause truncation of the file. A trailing F character can
     also  be  included  in  the  mode  argument  as described in
     fopen(3C) to enable extended FILE facility.


     The mode of the stream must be allowed by  the  file  access
     mode  of  the open file. The file position indicator associ-
     ated with the new stream is set to the position indicated by
     the file offset associated with the file descriptor.


     The fdopen() function preserves the  offset  maximum  previ-
     ously  set  for  the  open file description corresponding to
     fildes.


     The error and end-of-file  indicators  for  the  stream  are
     cleared.  The fdopen() function may cause the statime field
     of the underlying file to be marked for update.



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Standard C Library Functions                           fdopen(3C)



     If fildes refers to a shared memory object,  the  result  of
     the fdopen() function is unspecified.

RETURN VALUES
     Upon successful completion, fdopen() returns a pointer to  a
     stream.  Otherwise,  a null pointer is returned and errno is
     set to indicate the error.


     The fdopen() function may fail and not set  errno  if  there
     are no free stdio streams.

ERORS
     The fdopen() function may fail if:

     EBADF     The fildes argument is not a valid  file  descrip-
               tor.


     EINVAL    The mode argument is not a valid mode.


     EMFILE    {FOPENMAX} streams are currently open in the cal-
               ling process.

               {STREAMAX} streams are  currently  open  in  the
               calling process.


     ENOMEM    There is insufficient space to allocate a buffer.


USAGE
     A process is allowed to  have  at  least  {FOPENMAX}  stdio
     streams  open  at  a time. For 32-bit applications, however,
     the underlying ABIs formerly required that no file  descrip-
     tor used to access the file underlying a stdio stream have a
     value greater than 255.  To  maintain  binary  compatibility
     with  earlier  Solaris releases, this limit still constrains
     32-bit applications.


     File descriptors  are  obtained  from  calls  like  open(2),
     dup(2),  creat(2)  or  pipe(2),  which open files but do not
     return streams. Streams are necessary input for  almost  all
     of the standard I/O library functions.

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





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Standard C Library Functions                           fdopen(3C)



     
           ATRIBUTE TYPE               ATRIBUTE VALUE       
    
     Interface Stability          See below.                  
    
     MT-Level                     MT-Safe                     
    



     The F character in the mode argument  is  Evolving.  In  all
     other respects this function is Standard.

SEE ALSO
     creat(2), dup(2), open(2), pipe(2),  fclose(3C),  fopen(3C),
     attributes(5), standards(5)







































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