NAME
grantpt
—
grant access to a slave pseudo-terminal
device
LIBRARY
library “libc”
SYNOPSIS
#include
<stdlib.h>
int
grantpt
(int
fildes);
DESCRIPTION
Thegrantpt
()
function changes the mode and ownership of the slave pseudo-terminal device
that corresponds to the master pseudo-terminal device associated with
fildes to be owned by the real user id of the calling
process, group id of tty
. The permissions are set to
readable and writable by owner, and writable by group. If the slave
pseudo-terminal device was being accessed by other file descriptors at the
time, all such access will be revoked.
RETURN VALUES
If successful, grantpt
() returns 0;
otherwise a value of -1 is returned and errno is set
to indicate the error.
ERRORS
The grantpt
() function will fail if:
- [
EACCESS
] - the corresponding pseudo-terminal device could not be accessed.
- [
EBADF
] - fildes is not a valid descriptor.
- [
EINVAL
] - fildes is not associated with a master pseudo-terminal device.
NOTES
Setting the group to tty
and revoking
accesses by other file descriptors are NetBSD
extensions. Calling grantpt
() is equivalent to:
ioctl(fildes, TIOCGRANTPT, 0);
SEE ALSO
STANDARDS
The grantpt
() function conforms to
IEEE Std 1003.1-2001 (“POSIX.1”). Its
first release was in X/Open Portability Guide
Issue 4, Version 2 (“XPG4.2”).