122123Smckusick /* 222123Smckusick * Copyright (c) 1985 Regents of the University of California. 335306Sbostic * All rights reserved. 435306Sbostic * 542627Sbostic * %sccs.include.redist.c% 622123Smckusick */ 718339Sserge 826609Sdonn #if defined(LIBC_SCCS) && !defined(lint) 9*46597Sdonn static char sccsid[] = "@(#)ualarm.c 5.5 (Berkeley) 02/23/91"; 1035306Sbostic #endif /* LIBC_SCCS and not lint */ 1122123Smckusick 1218339Sserge #include <sys/time.h> 13*46597Sdonn #include <unistd.h> 1418339Sserge 1518339Sserge #define USPS 1000000 /* # of microseconds in a second */ 1618339Sserge 1718339Sserge /* 1818339Sserge * Generate a SIGALRM signal in ``usecs'' microseconds. 1918339Sserge * If ``reload'' is non-zero, keep generating SIGALRM 2018339Sserge * every ``reload'' microseconds after the first signal. 2118339Sserge */ 2218339Sserge unsigned 2318339Sserge ualarm(usecs, reload) 2418339Sserge register unsigned usecs; 2518339Sserge register unsigned reload; 2618339Sserge { 2718339Sserge struct itimerval new, old; 2818339Sserge 2918339Sserge new.it_interval.tv_usec = reload % USPS; 3018339Sserge new.it_interval.tv_sec = reload / USPS; 3118339Sserge 3218339Sserge new.it_value.tv_usec = usecs % USPS; 3318339Sserge new.it_value.tv_sec = usecs / USPS; 3418339Sserge 3518339Sserge if (setitimer(ITIMER_REAL, &new, &old) == 0) 3618339Sserge return (old.it_value.tv_sec * USPS + old.it_value.tv_usec); 3718339Sserge /* else */ 3818339Sserge return (-1); 3918339Sserge } 40