Provided by: manpages-dev_3.27-1ubuntu2_all
unlockpt - unlock a pseudo-terminal master/slave pair
int unlockpt(int fd);
The unlockpt() function unlocks the slave pseudo-terminal device (pty)
corresponding to the master pty referred to by fd.
unlockpt() should be called before opening the slave side of a pty.
When successful, unlockpt() returns 0. Otherwise, it returns -1 and
sets errno appropriately.
EBADF The fd argument is not a file descriptor open for writing.
EINVAL The fd argument is not associated with a master pty.
unlockpt() is provided in glibc since version 2.1.
grantpt(3), posix_openpt(3), ptsname(3), pts(4),
This page is part of release 3.27 of the Linux man-pages project. A
description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.