man(1) Manual page archive

     FSEEK(3S)                                               FSEEK(3S)

          fseek, ftell, rewind - reposition a stream

          #include <stdio.h>

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

          long ftell(stream)
          FILE *stream;


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

          Fseek undoes any effects of ungetc(3).

          Ftell returns the current value of the offset relative to
          the beginning of the file associated with the named stream.
          It is measured in bytes on UNIX; on some other systems it is
          a magic cookie, and the only foolproof way to obtain an
          offset for fseek.

          Rewind(stream) is equivalent to fseek(stream, 0L, 0).

          lseek(2), fopen(3)

          Fseek returns -1 for improper seeks.