fdopen(3C)						   Standard C Library Functions 						fdopen(3C)

NAME

       fdopen - associate a stream with a file descriptor

SYNOPSIS

       #include <stdio.h>

       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 associated 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 previously 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 st_atime field of the underlying  file
       to be marked for update.

       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.

ERRORS

       The fdopen() function may fail if:

       EBADF	 The fildes argument is not a valid file descriptor.

       EINVAL	 The mode argument is not a valid mode.

       EMFILE	 {FOPEN_MAX} streams are currently open in the calling process.

		 {STREAM_MAX} 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 {FOPEN_MAX} stdio streams open at a time. For 32-bit applications, however, the underlying ABIs  for-
       merly  required that no file descriptor 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.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE 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)

SunOS 5.11							    18 Apr 2006 							fdopen(3C)