centos man page for unlockpt

UNLOCKPT(3P)						     POSIX Programmer's Manual						      UNLOCKPT(3P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
       unlockpt - unlock a pseudo-terminal master/slave pair

SYNOPSIS
       #include <stdlib.h>

       int unlockpt(int fildes);

DESCRIPTION
       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.

RETURN VALUE
       Upon successful completion, unlockpt() shall return 0. Otherwise, it shall return -1 and set errno to indicate the error.

ERRORS
       The unlockpt() function may fail if:

       EBADF  The fildes argument is not a file descriptor open for writing.

       EINVAL The fildes argument is not associated with a master pseudo-terminal device.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       None.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       grantpt(), open(), ptsname(), the Base Definitions volume of IEEE Std 1003.1-2001, <stdlib.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
       Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and  the  original  IEEE
       and  The  Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained
       online at http://www.opengroup.org/unix/online.html .

IEEE
/The Open Group						       2003							      UNLOCKPT(3P)