From 445ebb943f6f44e1731d59873d839633e33bb7a1 Mon Sep 17 00:00:00 2001 From: Karl Heuer Date: Sat, 5 Jun 1999 01:13:36 +0000 Subject: [PATCH] (get_boot_time): Don't look at /proc/uptime; it doesn't work if the system date is changed, or if the system is suspended. Look at the last-modified time of /var/run/random-seed instead. --- src/filelock.c | 41 +++++------------------------------------ 1 file changed, 5 insertions(+), 36 deletions(-) diff --git a/src/filelock.c b/src/filelock.c index 2f880d10d2d..9217b58f188 100644 --- a/src/filelock.c +++ b/src/filelock.c @@ -112,50 +112,19 @@ extern Lisp_Object Vshell_file_name; static time_t get_boot_time () { - struct utmp ut, *utp; - int fd; - EMACS_TIME time_before, after; int counter; + struct stat st; if (boot_time_initialized) return boot_time; boot_time_initialized = 1; - EMACS_GET_TIME (time_before); - - /* Try calculating the last boot time - from the uptime as obtained from /proc/uptime. - - This has a disadvantage in that if the system time has been - changed (say to correct the clock), - then current_time - uptime != wtmp_boot_time. - However, the speedup from doing this can be so great - that I think it is worth that problem occasionally. */ - - while ((fd = open ("/proc/uptime", O_RDONLY)) >= 0) + if (stat ("/var/run/random-seed", &st) == 0) { - char buf[100]; - int res; - double upsecs; - time_t uptime; - - read (fd, buf, sizeof buf); - close (fd); - - res = sscanf (buf, "%lf", &upsecs); - - /* If the current time did not tick while we were getting the - uptime, we have a valid result. */ - EMACS_GET_TIME (after); - if (res == 1 && EMACS_SECS (after) == EMACS_SECS (time_before)) - { - boot_time = EMACS_SECS (time_before) - (time_t) upsecs; - return boot_time; - } - - /* Otherwise, try again to read the uptime. */ - time_before = after; + boot_time = st.st_mtime; + return boot_time; } + #if defined (CTL_KERN) && defined (KERN_BOOTTIME) { int mib[2]; -- 2.39.5