TIOCGLCKTRMIOS, TIOCSLCKTRMIOS

Standard C library (libc, -lc)

#include <asm/termbits.h>  /* Definition of TIOC*CLKTRMIOS constants */
#include <sys/ioctl.h>

int ioctl(int fd, TIOCGLCKTRMIOS, struct termios *argp);
int ioctl(int fd, TIOCSLCKTRMIOS, const struct termios *argp);

#include <asm/termbits.h>

struct termios;

The termios structure of a terminal can be locked. The lock is itself a termios structure, with nonzero bits or fields indicating a locked value.

TIOCGLCKTRMIOS

Gets the locking status of the termios structure of the terminal.

TIOCSLCKTRMIOS

Sets the locking status of the termios structure of the terminal. Only a process with the CAP_SYS_ADMIN capability can do this.

On success, 0 is returned. On error, -1 is returned, and errno is set to indicate the error.

EPERM

Insufficient permission.

Please note that struct termios from <asm/termbits.h> is different and incompatible with struct termios from <termios.h>. These ioctl calls require struct termios from <asm/termbits.h>.

ioctl(2), ioctl_tty(2), TCSETS(2const)