From 2730a7d64953d47c8097260b6bd45ca8277644fd Mon Sep 17 00:00:00 2001 From: Pierre-Marc Fournier Date: Tue, 13 Oct 2009 19:09:27 -0400 Subject: [PATCH] ustd: add support for --pidfile --- ustd/ustd.c | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/ustd/ustd.c b/ustd/ustd.c index 0019776..6d8680c 100644 --- a/ustd/ustd.c +++ b/ustd/ustd.c @@ -53,6 +53,7 @@ char *sock_path=NULL; char *trace_path=NULL; int daemon_mode = 0; +char *pidfile = NULL; /* Number of active buffers and the mutex to protect it. */ int active_buffers = 0; @@ -516,6 +517,9 @@ int parse_args(int argc, char **argv) case 'd': daemon_mode = 1; break; + case 'p': + pidfile = strdup(optarg); + break; case 'h': usage(); exit(0); @@ -654,10 +658,11 @@ int start_ustd_daemon() { int result; int fd[2]; + pid_t child_pid; result = pipe(fd); - result = fork(); + result = child_pid = fork(); if(result == -1) { PERROR("fork"); return -1; @@ -667,6 +672,27 @@ int start_ustd_daemon() } else { char buf; + FILE *pidfp; + + /* It's important to write the file *before* + * the parent ends, because the file may be + * read as soon as the parent ends. + */ + if(pidfile) { + pidfp = fopen(pidfile, "w+"); + if(!pidfp) { + PERROR("fopen (%s)", pidfile); + WARN("killing child process"); + result = kill(child_pid, SIGTERM); + if(result == -1) { + PERROR("kill"); + } + return -1; + } + + fprintf(pidfp, "%d\n", child_pid); + fclose(pidfp); + } result = read(fd[0], &buf, 1); if(result == -1) { -- 2.34.1