May 25, 2004 GRANTPT 3

### NAME

grantpt - grant access to a slave pseudo-terminal device

### LIBRARY

Standard C Library (libc, -lc)

### SYNOPSIS

```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);

`

### SEE ALSO

ioctl(2), posix_openpt(3), ptsname(3), unlockpt(3)

### 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'') .