unlockpt - unlock a pseudo-terminal master/slave pair
The unlockpt() function shall unlock the slave pseudo-terminal device associated with the master to which fildes refers.
Conforming applications shall ensure that they call unlockpt() before opening the slave side of a pseudo-terminal device.
Upon successful completion, unlockpt() shall return 0. Otherwise, it shall return -1 and set 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.
grantpt(), open(), ptsname(), the Base Definitions volume of IEEE Std 1003.1-2001, <stdlib.h>
First released in Issue 4, Version 2.
Moved from X/OPEN UNIX extension to BASE.
The DESCRIPTION is updated to avoid use of the term "must" for application requirements.