[syslog-ng] strange problem when use "_" in the destination log file name

[Balazs Scheidler]

On Wed, 2005-08-03 at 16:01 -0700, Arnold Wang wrote:
> Hi,
> I'm running into a strange problem with syslog-ng 1.6.8 on RHEL 4. In my
> configuration file, I have the following local log file defined:
> destination d_file { file("/var/syslog-
> ng/HOSTS/$HOST/$YEAR/$MONTH/$HOST_$MONTH$DAY.log" owner(root) group
> (root) perm(0600) dir_perm(0700) create_dirs(yes)); }; 
> However, the log file generated by the syslog-ng for today is named
> "0803.log", which is different than "hostname_0803.log" as I expected. 
> I tried using escape "\" so it looks like "$HOST\_$MONTH$DAY.log" and it
> didn't help at all. This problem actually doesn't bother me that much. I
> changed "_" to "-" or ".", it worked. I'm just curious about this. 

The performance of macro expansion was improved sometime during the end
of the 1.5.x series, which makes syslog-ng extract the macro name first,
and then looking up the macro name using a gperf generated hash.

The character set of words in syslog-ng is [A-Z0-9_], therefore it uses
_ as part of a word.

Syslog-ng 1.9.x improves on the situation by permitting the use of shell
like ${macro} expansion, where you could write:

${macro}_${othermacro}

and so on.

-- 
Bazsi