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NAME

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

SYNOPSIS

       #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

       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
       end-of-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

       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 errno is set to indicate the
       error.

ERRORS

       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  functions 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

       C89, C99.

SEE ALSO

       lseek(2), fseeko(3)

COLOPHON

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       description of the project, and information about reporting  bugs,  can
       be found at http://www.kernel.org/doc/man-pages/.