From 624188aec0e730375bb782a45ab3224b33dd30e9 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Tue, 19 Feb 2008 18:26:40 +0000 Subject: [PATCH] microcom: tiny shrink, adding comments --- miscutils/microcom.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/miscutils/microcom.c b/miscutils/microcom.c index ea48291ae..3c573eaa9 100644 --- a/miscutils/microcom.c +++ b/miscutils/microcom.c @@ -51,18 +51,17 @@ int microcom_main(int argc, char **argv) enum { OPT_X = 1 << 0, // do not respect Ctrl-X, Ctrl-@ OPT_s = 1 << 1, // baudrate - OPT_d = 1 << 2, // wait for device response, msecs + OPT_d = 1 << 2, // wait for device response, ms OPT_t = 1 << 3, // timeout, ms }; speed_t speed = 9600; int delay = -1; int timeout = -1; + unsigned opts; // fetch options - unsigned opts; - opt_complementary = "=1:s+:d+:t+"; // exactly one arg should be there + opt_complementary = "=1:s+:d+:t+"; // exactly one arg, numeric options opts = getopt32(argv, "Xs:d:t:", &speed, &delay, &timeout); - // argc -= optind; argv += optind; @@ -71,14 +70,16 @@ int microcom_main(int argc, char **argv) device_lock_file = xasprintf("/var/lock/LCK..%s", device_lock_file); sfd = open(device_lock_file, O_CREAT | O_WRONLY | O_TRUNC | O_EXCL, 0644); if (sfd < 0) { + // device already locked -> bail out if (errno == EEXIST) bb_perror_msg_and_die("can't create %s", device_lock_file); + // can't create lock -> don't care if (ENABLE_FEATURE_CLEAN_UP) free(device_lock_file); device_lock_file = NULL; - } - if (sfd > 0) { - // %4d to make mgetty happy. It treats 4-bytes lock files as binary, + } else { + // %4d to make concurrent mgetty (if any) happy. + // Mgetty treats 4-bytes lock files as binary, // not text, PID. Making 5+ char file. Brrr... char *s = xasprintf("%4d\n", getpid()); write(sfd, s, strlen(s)); -- 2.25.1