4 /* MAXHOSTNAMELEN is in sys/param.h */
5 #define MAXHOSTNAMELEN 64
7 char lockstring[MAXHOSTNAMELEN+8];
10 main(int argc, char *argv[]) {
16 fprint(2, "usage: LOCK lockfile hostname ppid\n");
17 exits("lock failed on usage");
20 if ((fd=create(lockfile, OLOCK|ORDWR, 0666)) < 0) {
21 exits("lock failed on create");
24 ssize = sprint(lockstring, "%s %s\n", argv[2], argv[3]);
25 if (write(fd, lockstring, ssize) != ssize) {
26 fprint(2, "LOCK:write(): %r\n");
27 exits("lock failed on write to lockfile");
36 fprint(2, "LOCK:fork(): %r\n");
37 exits("lock failed on fork");
41 statbuf = dirfstat(fd);
44 if (statbuf->length == 0){
49 if (write(fd, "", 0) < 0)
55 postnote(PNGROUP, ppid, "kill");