#include <stdlib.h> #include <unistd.h> #include <stdio.h> #include <string.h> #include <utmp.h> int main(int argc, char **argv) { struct utmp utmp; if (argc <= 1) { fprintf(stderr, "need an argument\n"); return 1; } memset(&utmp, 0, sizeof(utmp)); utmp.ut_type = RUN_LVL; utmp.ut_pid = argv[1][0]; setutent(); pututline(&utmp); endutent(); return 0; }