Joachim Wiberg
00794d41bc
The block conversion changed the bodies of the reference sections but left every "**Syntax:**" header spelling the line-based format, so each page opened by teaching the format it then stopped using. Six files were missed entirely: runparts, files, capabilities, requirements, runlevels, and switchroot. runparts had no block spelling written down anywhere, though the parser has read `runparts`, `runparts-progress`, and `runparts-sysv` all along. tty gains a table per variant. Its three syntax lines carried nine positional fields between them, which no longer describes anything the parser accepts. Fixes #148 Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
2.3 KiB
General Logging
Syntax: log { size = 200k count = 5 }
Log rotation for run/task/services using the log sub-option with
redirection to a log file. Global setting, applies to all services.
The size can be given as bytes, without a specifier, or in k, M,
or G, e.g. size = 10M, or size = 3G. A value of size = 0 disables
log rotation. The default is 200k.
The count value is recommended to be between 1-5, with a default 5. Setting count to 0 means the logfile will be truncated when the MAX size limit is reached.
Redirecting Output
The run, task, and service stanzas also allow the keyword log to
redirect stderr and stdout of the application to a file or syslog
using the native logit tool. This is useful for programs that do not
support syslog on their own, which is sometimes the case when running
in the foreground.
The full syntax is:
log:/path/to/file
log:prio:facility.level,tag:ident
log:console
log:null
log
Default prio is daemon.info and default tag is the basename of the
service or run/task command.
Log rotation is controlled using the global log setting.
Example:
service ntpd {
description = "NTP daemon"
log {
priority = "user.warn"
identity = "ntpd"
}
command = "/sbin/ntpd pool.ntp.org"
}
Output Buffering
When using the log block, Finit redirects the service's stdout and
stderr to a pipe connected to a logger process. Programs detect this as
non-interactive output (i.e., isatty() returns false) and typically
switch from line-buffered to fully-buffered mode.
Most well-behaved daemons explicitly flush their output or use syslog
directly, so this is rarely an issue. However, if a service's log
messages appear delayed or batched, you can force line-buffered output
by wrapping the command with stdbuf:
service myservice {
description = "My service"
log { }
command = "/usr/bin/stdbuf -oL /path/to/command"
}
The -oL option forces line-buffered output, and -o0 forces unbuffered
output. See stdbuf(1) for details.
Note
Using
stdbufis rarely necessary. Only use it if you observe actual buffering issues with a specific service.