fseek(3s)                  DG/UX 4.30                   fseek(3s)



     NAME
          fseek, rewind, fgetpos, fsetpos, ftell - reposition a file
          pointer in a stream

     SYNOPSIS
          #include <stdio.h>

          int fseek (stream, offset, ptrname)
          FILE *stream;
          long offset;
          int ptrname;

          void rewind (stream)
          FILE *stream;

          int fgetpos (stream, pos)
          FILE *stream;
          fpost *pos;

          int fsetpos (stream, pos)
          FILE *stream;
          fpost *pos;

          long ftell (stream)
          FILE *stream;

     DESCRIPTION
          Fseek sets the position of the next input or output
          operation on the stream.  The new position is at the signed
          distance offset bytes from the beginning, from the current
          position, or from the end of the file, according as ptrname
          has the value 0, 1, or 2.

          Rewind(stream) is equivalent to fseek(stream, 0L, 0), except
          that no value is returned.

          Fgetpos stores the current value of the file position
          indicator for stream in the object pointed to by pos.  This
          value can be used in a subsequent call to fsetpos to
          reposition the stream to this position.

          Fsetpos sets the file position indicator for stream to the
          value of the object pointed to by pos; this value must have
          been obtained by an earlier call to fgetpos.

          Fseek, rewind, and fsetpos undo any effects of ungetc(3S).

          After fseek, rewind, or fsetpos the next operation on a file
          opened for update may be either input or output.

          Ftell returns the offset of the current byte relative to the
          beginning of the file associated with the named stream.



     Licensed material--property of copyright holder(s)         Page 1

     fseek(3s)                  DG/UX 4.30                   fseek(3s)



     SEE ALSO
          lseek(2), fopen(3S), popen(3S), stdio(3S), ungetc(3S).

     DIAGNOSTICS
          fseek returns non-zero for improper seeks, otherwise zero.
          An improper seek can be, for example, an fseek done on a
          file that has not been opened via fopen; in particular,
          fseek may not be used on a terminal, or on a file opened via
          popen(3S).  If the file has not been opened, errno is set to
          EBADF along with a non-zero return value.

          Fgetpos and fsetpos return zero if successful, otherwise
          non-zero.

     WARNING
          Although on the UNIX system an offset returned by ftell is
          measured in bytes, and it is permissible to seek to
          positions relative to that offset, portability to non-UNIX
          systems requires that an offset be used by fseek directly.
          Arithmetic may not meaningfully be performed on such an
          offset, which is not necessarily measured in bytes.


































     Licensed material--property of copyright holder(s)         Page 2