TIOCSSOFTCAR(2const)                                      TIOCSSOFTCAR(2const)

NAME
       TIOCGSOFTCAR, TIOCSSOFTCAR - marking a line as local

LIBRARY
       Standard C library (libc, -lc)

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

       int ioctl(int fd, TIOCGSOFTCAR, int *argp);
       int ioctl(int fd, TIOCSSOFTCAR, const int *argp);

DESCRIPTION
       TIOCGSOFTCAR
              ("Get software carrier flag") Get the status of the CLOCAL flag
              in the c_cflag field of the termios structure.

       TIOCSSOFTCAR
              ("Set software carrier flag") Set the CLOCAL flag in the termios
              structure when *argp is nonzero, and clear it otherwise.

       If the CLOCAL flag for a line is off, the hardware carrier detect (DCD)
       signal is significant, and an open(2) of the corresponding terminal
       will block until DCD is asserted, unless the O_NONBLOCK flag is given.
       If CLOCAL is set, the line behaves as if DCD is always asserted.  The
       software carrier flag is usually turned on for local devices, and is
       off for lines with modems.

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

SEE ALSO
       ioctl(2), ioctl_tty(2)

Linux man-pages 6.9.1             2024-06-13              TIOCSSOFTCAR(2const)