unlockpt(3) Linux Man Page - System Grab Bag

Name

unlockpt - unlock a pseudoterminal master/slave pair

Standard C library ( libc ", " -lc )

#define _XOPEN_SOURCE 
#include <stdlib.h> 
int unlockpt(int  fd );

Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

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.

For an explanation of the terms used in this section, see attributes(7). allbox; lbx lb lb T{ unlockpt()

Interface	Attribute	Value
T}	Thread safety	MT-Safe

glibc 2.1. POSIX.1-2001.