NAME    [Toc]    [Back]

       fgetpos, fseek, fsetpos, ftell, rewind - reposition a stream

SYNOPSIS    [Toc]    [Back]

       #include <stdio.h>

       int fseek( FILE *stream, long offset, int whence);
       long ftell( FILE *stream);
       void rewind( FILE *stream);
       int fgetpos( FILE *stream, fpos_t *pos);
       int fsetpos( FILE *stream, fpos_t *pos);

DESCRIPTION    [Toc]    [Back]

       The  fseek  function  sets  the	file position indicator for the stream
       pointed to by stream.  The new position, measured in bytes, is obtained
       by  adding offset bytes to the position specified by whence.  If whence
       is set to SEEK_SET, SEEK_CUR, or SEEK_END, the offset  is  relative  to
       the  start of the file, the current position indicator, or end-of-file,
       respectively.  A successful call to the fseek function clears the  endof-file
	indicator  for	the  stream  and  undoes  any  effects	of the
       ungetc(3) function on the same stream.

       The ftell function obtains the current value of the file position indicator
 for the stream pointed to by stream.

       The  rewind  function  sets  the file position indicator for the stream
       pointed to by stream to the beginning of the file.   It	is  equivalent
       to:

	      (void)fseek(stream, 0L, SEEK_SET)

       except  that  the  error  indicator for the stream is also cleared (see
       clearerr(3)).

       The fgetpos and fsetpos functions are alternate	interfaces  equivalent
       to  ftell  and fseek (with whence set to SEEK_SET), setting and storing
       the current value of the file offset into or from the object referenced
       by  pos.   On  some  non-UNIX systems an fpos_t object may be a complex
       object and these routines may be the only way to portably reposition  a
       text stream.

RETURN VALUE    [Toc]    [Back]

       The  rewind  function  returns  no  value.  Upon successful completion,
       fgetpos, fseek, fsetpos return 0, and ftell returns the current offset.
       Otherwise, -1 is returned and the global variable errno is set to indicate
 the error.

ERRORS    [Toc]    [Back]

       EBADF  The stream specified is not a seekable stream.

       EINVAL The whence argument to fseek  was  not  SEEK_SET,  SEEK_END,  or
	      SEEK_CUR.

       The  function  fgetpos, fseek, fsetpos, and ftell may also fail and set
       errno for any of the  errors  specified	for  the  routines  fflush(3),
       fstat(2), lseek(2), and malloc(3).

CONFORMING TO    [Toc]    [Back]

       The  fgetpos,  fsetpos,	fseek,	ftell, and rewind functions conform to
       ANSI X3.159-1989 (``ANSI C'').

SEE ALSO    [Toc]    [Back]

       lseek(2)



BSD MANPAGE			  1993-11-29			      FSEEK(3)