unlockpt(3C)                                            unlockpt(3C)


       NAME
             unlockpt - unlock a pseudo-terminal master/slave pair

       SYNOPSIS
             #include <sys/ptms.h>
             int unlockpt(int fildes);

       DESCRIPTION
             The function unlockpt clears a lock flag associated with the
             slave pseudo-terminal device associated with its master
             pseudo-terminal counterpart so that the slave pseudo-terminal
             device can be opened.  fildes is a file descriptor returned
             from a successful open of a master pseudo-terminal device.

          Return Values
             Upon successful completion, the function unlockpt returns 0;
             otherwise it returns -1.

          Errors
             A failure may occur if fildes is not an open file descriptor
             or is not associated with a master pseudo-terminal device.

       REFERENCES
             grantpt(3C), open(2), ptsname(3C), pty(7)
























                           Copyright 1994 Novell, Inc.               Page 1