UNLOCKPT(3) Library Functions Manual UNLOCKPT(3)

unlockpt — unlock a pseudo-terminal master/slave pair

#include <stdlib.h>

int unlockpt(int fildes);

The unlockpt() function unlocks the slave pseudo-terminal device associated with the master to which fildes refers.

Portable applications must call before opening the slave side of a pseudo-terminal device.

Upon successful completion, unlockpt() returns 0. Otherwise, it returns -1 and sets errno to indicate the error.

The unlockpt() function may fail if:

The fildes argument is not a file descriptor open for writing.
The fildes argument is not associated with a master pseudo-terminal device.

None.

None.

None.

grantpt(3) , open(3) , ptsname(3) , <stdlib.h> .

February 1997 posix.fail