LSEEK(2)                GENIX Programmer's Manual                LSEEK(2)



      NAME
           lseek, tell - move read/write pointer

      SYNOPSIS
           long lseek(fildes, offset, whence)
           long offset;

           long tell(fildes)

      DESCRIPTION
           The file descriptor refers to a file open for  reading  or  writing.
           The read (resp. write) pointer for the file is set as follows:

                If whence is 0, the pointer is set to offset bytes.

                If whence is 1, the pointer is set to its current location plus
                offset.

                If whence is 2, the pointer is set to the size of the file plus
                offset.

           The returned value is the resulting pointer location.

           The obsolete function tell(fildes) is identical to lseek(fildes, 0L,
           1).

           Seeking far beyond the end of a file, then writing, creates a gap or
           `hole', which occupies no physical space and reads as zeros.

      SEE ALSO
           open(2), creat(2), fseek(3)

      DIAGNOSTICS
           -1 is returned for an undefined file descriptor, seek on a pipe,  or
           seek to a position before the beginning of file.

      BUGS
           Lseek is a no-op on character special files.

















      Printed 11/16/83                                                        1