unlockpt(3C)                                                   unlockpt(3C)


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

   SYNOPSIS
         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 VALUE
         Upon successful completion, the function unlockpt() returns 0;
         otherwise it returns -1. A failure may occur if fildes is not an open
         file descriptor or is not associated with a master pseudo-terminal
         device.

   SEE ALSO
         open(2)
         grantpt(3C), ptsname(3C).
         Programmer's Guide: STREAMS.






























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