ucspilogd
Software
www.skarnet.org

The ucspilogd program

ucspilogd acts as a filter, converting syslog facility numbers and alert levels into names.

Interface

     ucspilogd [ var ... ]

• ucspilogd reads a stream of syslog-like messages on stdin. Those messages can be newline-terminated or null-terminated.
• For every line it reads: if it has been given var arguments, it writes the value of every var environment variable, followed by a colon and a space.
• If the line begins with a syslog facility number and/or alert level in the syslog format, it converts them into a human-readable name in the syslogd fashion.
• It then writes the processed line to stdout.

Common use

You can emulate the whole syslogd behaviour by combining the following components:

• A Unix stream super-server such as s6-ipcserver or ipcserver, listening to the Unix domain socket /dev/log, to connect to the kernel log-reading interface.
• ucspilogd running under that super-server, to read the logs and perform adequate transformations.
• A logger such as s6-log, multilog or svlogd, to store the logs into the filesystem.
• A supervision mechanism such as s6, daemontools or runit, to ensure ease of use and reliability of the whole chain.

The resulting suite of programs is still smaller, and way more reliable, than a standard syslogd.

In the service subdirectory of the ucspilogd package, you will find a suitable ucspilogd service directory usable with s6, daemontools or runit. The run scripts are written in the execline language.

Using ucspilogd as a klogd replacement

Certain Unix kernels offer a nice interface to the kernel logs. For instance, the Linux kernel provides the /proc/kmsg fake file, that can be opened and read like a normal file, excepts that it gives the kernel logs when they are available and blocks otherwise. You can use ucspilogd to process data from those interfaces.

The service/klogd-linux subdirectory of the ucspilogd package is a service directory providing such a klogd service for Linux, using the /proc/kmsg interface.