| GRANTPT(3) | Library Functions Manual | GRANTPT(3) | 
NAME
 grantpt — grant access to a slave pseudo-terminal device
LIBRARY
 Standard C Library (libc, -lc)
SYNOPSIS
 #include <stdlib.h>
int
grantpt(int fildes);
 
DESCRIPTION
 The grantpt() 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);
 
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”).