unlockpt - unlock a pseudoterminal master/slave pair
Standard C library (
libc,
-lc)
#define _XOPEN_SOURCE
#include <stdlib.h>
int unlockpt(int fd);
unlockpt():
Since glibc 2.24:
_XOPEN_SOURCE >= 500
glibc 2.23 and earlier:
_XOPEN_SOURCE
The
unlockpt() function unlocks the slave pseudoterminal device
corresponding to the master pseudoterminal referred to by the file descriptor
fd.
unlockpt() should be called before opening the slave side of a
pseudoterminal.
When successful,
unlockpt() returns 0. Otherwise, it returns -1 and sets
errno to indicate the error.
- EBADF
- The fd argument is not a file descriptor open for
writing.
- EINVAL
- The fd argument is not associated with a master
pseudoterminal.
unlockpt() is provided since glibc 2.1.
For an explanation of the terms used in this section, see
attributes(7).
Interface |
Attribute |
Value |
unlockpt () |
Thread safety |
MT-Safe |
POSIX.1-2001, POSIX.1-2008.
grantpt(3),
posix_openpt(3),
ptsname(3),
pts(4),
pty(7)