lseek(2)                   DG/UX 4.30                    lseek(2)



     NAME
          lseek - Change object pointer's current position.

     SYNOPSIS
          #include <sys/file.h>
          #include <sys/types.h>
          #include <unistd.h>

          off_t  lseek  (fildes, offset, whence)
          int             fildes;
          off_t           offset;
          int             whence;

     PARAMETERS
          fildes         A valid, active file descriptor.

          offset         The new position of the file pointer.

          whence         Changes the interpretation of offset.

     DESCRIPTION
          If fildes is a valid, active descriptor that refers to an
          object pointer having a current position attribute, the
          object pointer's current position is modified according to
          the offset and whence parameters as follows:

               If whence is SEEK_SET, the current position is set to
               offset bytes.

               If whence is SEEK_CUR, the current position is set to
               its current location plus offset .

               If whence is SEEK_END, the current position is set to
               the size of the object plus offset.  The size of
               character special files and block special files is
               always zero.  Hence, this option is equivalent to
               whence being SEEK_SET for these files.

               If whence is equal to any other value, the user is sent
               the signal SIGSYS and errno returns EINVAL.

          It is an error for the new current position attribute to be
          negative.

          If lseek fails, the object pointer is not changed.

     ACCESS CONTROL
          None.

     RETURN VALUE
          position       Completed successfully.  The object pointer's
                         new position is returned.



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

     lseek(2)                   DG/UX 4.30                    lseek(2)



          -1             An error occurred.  Errno is set to indicate
                         the error.

     EXCEPTIONS
          Errno may be set to one of the following error codes:

          EBADF          Fildes is not a valid, active descriptor.

          ESPIPE         Fildes is associated with a pipe or a socket.

          EINVAL with SIGSYS signal
                         Whence is not SEEK_SET, SEEK_CUR, or
                         SEEK_END.

          EINVAL         The resulting file pointer would be negative.

     SEE ALSO
          creat(2), dup(2), dup2(2), fcntl(2), open(2).





































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