UNLOCKPT

Section: POSIX Programmer's Manual (3P)
Updated: 2017
Page Index
 

PROLOG

This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding 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

See the RATIONALE section for posix_openpt().  

FUTURE DIRECTIONS

None.  

SEE ALSO

grantpt(), open(), posix_openpt(), ptsname()

The Base Definitions volume of POSIX.1-2017, <stdlib.h>  

COPYRIGHT

Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1-2017, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 7, 2018 Edition, Copyright (C) 2018 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 .

Any typographical or formatting errors that appear in this page are most likely to have been introduced during the conversion of the source files to man page format. To report such errors, see https://www.kernel.org/doc/man-pages/reporting_bugs.html .


 

Index

PROLOG
NAME
SYNOPSIS
DESCRIPTION
RETURN VALUE
ERRORS
EXAMPLES
APPLICATION USAGE
RATIONALE
FUTURE DIRECTIONS
SEE ALSO
COPYRIGHT