| Logging and backgrounding |
| |
| By default, bb_[p]error_msg[_and_die] messages go to stderr, |
| and of course, usually applets do not auto-background. :) |
| |
| Historically, daemons and inetd services are different. |
| |
| Busybox is trying to provide compatible behavior, thus if an applet |
| is emulating an existing utility, it should mimic it. If utility |
| auto-backgrounds itself, busybox applet should do the same. |
| If utility normally logs to syslog, busybox applet should do |
| the same too. |
| |
| However, busybox should not needlessly restrict the freedom |
| of the users. And users have different needs and different preferences. |
| Some might like logging everything from daemons to syslog. |
| Others prefer running stuff under runsv/svlogd and thus would like |
| logging to stderr and no daemonization. |
| |
| To help with that, busybox applets should have options to override |
| default behavior, whatever that is for a given applet. |
| |
| |
| Current situation is a bit of a mess: |
| |
| acpid - auto-backgrounds unless -d |
| crond - auto-backgrounds unless -f, logs to syslog unless -d or -L. |
| option -d logs to stderr, -L FILE logs to FILE |
| devfsd - (obsolete) |
| dnsd - option -d makes it background and log to syslog |
| fakeidentd - inetd service. Auto-backgrounds and logs to syslog |
| if no -f and no -i and no -w (-i is "inetd service" flag, |
| -w is "inetd-wait service" flag) |
| ftpd - inetd service. Logs to syslog with -S, with -v logs to strerr too |
| httpd - auto-backgrounds unless -f or -i (-i is "inetd service" flag) |
| inetd - auto-backgrounds unless -f, logs to syslog unless -e |
| klogd - auto-backgrounds unless -n |
| syslogd - auto-backgrounds unless -n |
| telnetd - auto-backgrounds unless -f or -i (-i is "inetd service" flag) |
| udhcpc - auto-backgrounds unless -f after lease is obtained, |
| option -b makes it background sooner (when lease attempt |
| fails and retries start), |
| after backgrounding it stops logging to stderr; |
| logs to stderr, but option -S makes it log *also* to syslog |
| udhcpd - auto-backgrounds and do not log to stderr unless -f, |
| otherwise logs to stderr, but option -S makes it log *also* to syslog |
| zcip - auto-backgrounds and logs *also* to syslog unless -f |
| |
| Total: 13 applets (+1 obsolete), |
| 4 log to syslog by default (crond fakeidentd inetd zcip), |
| 5 never log to syslog (acpid httpd telnetd klogd syslogd, last two |
| - for obviously correct reasons), |
| there are no daemons which always log to syslog, |
| 12 auto-background if not run as inetd services (all except dnsd. |
| Note that there is no "standard" dnsd AFAIKS). But see below |
| for daemons (tcpsvd etc) which don't auto-background. |
| |
| miscutils/crond.c: logmode = LOGMODE_SYSLOG; |
| networking/dnsd.c: logmode = LOGMODE_SYSLOG; |
| networking/ftpd.c: logmode = LOGMODE_NONE; |
| networking/ftpd.c: logmode |= LOGMODE_SYSLOG; |
| networking/inetd.c: logmode = LOGMODE_SYSLOG; |
| networking/isrv_identd.c: logmode = LOGMODE_SYSLOG; |
| networking/telnetd.c: logmode = LOGMODE_SYSLOG; |
| networking/udhcp/dhcpc.c: logmode = LOGMODE_NONE; |
| networking/udhcp/dhcpc.c: logmode |= LOGMODE_SYSLOG; |
| networking/udhcp/dhcpc.c: logmode &= ~LOGMODE_STDIO; |
| networking/udhcp/dhcpd.c: logmode = LOGMODE_NONE; |
| networking/udhcp/dhcpd.c: logmode |= LOGMODE_SYSLOG; |
| networking/zcip.c: logmode |= LOGMODE_SYSLOG; |
| |
| |
| These daemons never auto-background and never log to syslog: |
| |
| lpd - inetd service. Has nothing to log so far, though |
| dhcprelay - standard behavior |
| inotifyd - standard behavior |
| runsv - standard behavior |
| runsvdir - standard behavior |
| svlogd - standard behavior |
| tcpsvd, udpsvd - standard behavior |
| tftpd - standard behavior |
| |
| |
| Non-daemons (seems to be use syslog for a good reason): |
| |
| networking/nameif.c: logmode |= LOGMODE_SYSLOG; |
| loginutils/chpasswd.c: logmode = LOGMODE_BOTH; |
| loginutils/chpasswd.c: logmode = LOGMODE_STDIO; |
| loginutils/getty.c: logmode = LOGMODE_BOTH; |
| loginutils/getty.c: logmode = LOGMODE_NONE; |
| loginutils/passwd.c: logmode = LOGMODE_STDIO; |
| loginutils/passwd.c: logmode = LOGMODE_BOTH; |
| loginutils/sulogin.c: logmode = LOGMODE_SYSLOG; (used if stdio isn't a tty) |
| loginutils/sulogin.c: logmode = LOGMODE_BOTH; |
| util-linux/mount.c: logmode = LOGMODE_SYSLOG; (used in a backgrounded NFS mount helper) |