GRANTPT(3C) Standard C Library Functions GRANTPT(3C)

grantptgrant access to the subsidiary device of a pseudo-terminal

#include <stdlib.h>

int
grantpt(int fildes);

The () function changes the mode and ownership of the pseudo-terminal subsidiary device associated with its pseudo-terminal manager counterpart.

The fildes argument is the file descriptor returned from a successful open(2) of the pseudo-terminal manager device; e.g., by calling posix_openpt(3C) or by performing an open(2) of the ptm(4D) device.

The user ID owner of the subsidiary device is set to the real user ID of the calling process. The group ID owner is set to a reserved group.

The permission mode of the subsidiary device is set to be readable and writable by the owner, and writable by the group.

The grantpt() function returns the value 0 if successful; otherwise the value -1 is returned and the global variable errno is set to indicate the error.

See posix_openpt(3C) for an example that includes a call to grantpt().

The grantpt() function may fail if:

The fildes argument is not a valid open file descriptor.
The fildes argument is not associated with a pseudo-terminal manager device.
The corresponding pseudo-terminal subsidiary device could not be accessed.

open(2), posix_openpt(3C), ptsname(3C), unlockpt(3C), ptm(4D), attributes(7), standards(7)

February 5, 2022 OmniOS