The grantpt() function shall change the mode and ownership of the slave
pseudo-terminal device associated with its master pseudo-terminal counterpart.
The fildes argument is a file descriptor that refers to a master
pseudo-terminal device. The user ID of the slave shall be set to the real UID
of the calling process and the group ID shall be set to an unspecified group
ID. The permission mode of the slave pseudo-terminal shall be set to readable
and writable by the owner, and writable by the group.
The behavior of the grantpt() function is unspecified if the application
has installed a signal handler to catch SIGCHLD signals.
Portions of this text are reprinted and reproduced in electronic form from IEEE
Std 1003.1, 2003 Edition, Standard for Information Technology -- 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