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).