ref: c6542b41f37be02049b88b2021ab1a62065c3613
dir: /sys/src/libc/port/hangup.c/
#include <u.h>
#include <libc.h>
#include <ctype.h>
/*
* force a connection to hangup
*/
int
hangup(int ctl)
{
return write(ctl, "hangup", sizeof("hangup")-1) != sizeof("hangup")-1;
}