.TH log 7 "May 2007" BUGLE "User manual"
.SH NAME
log \- configure logging output from other filter-sets
.SH SYNOPSIS
.nf
filterset log
{
    filename "bugle.log"
    file_level 4
    stderr_level 3
    flush "no"
    format "[%l] %f.%e: %m"
}
.fi
.SH DESCRIPTION
The log filter-set does not do any logging itself; instead, it provides
logging services to other filter-sets. It is always loaded, but it may be
explicitly listed in the configuration file to set options. The log is always
written to standard error, but it can be written to file as well. It is also
possible to control the log level.
.SH OPTIONS
.TP
.B filename
This sets the file for logging. Logging is still done to standard error. Note
that with the default settings, the file log is more verbose than the standard
error log.
.TP
.B flush
If this boolean is enabled (it is not by default) then the log is flushed to
disk after every entry. This may be required to obtain a complete log
if the program crashes.
.TP
.B file_level
The log level for the log file, where a higher number means more verbose
logging. The levels are
.RS
.TP
.B 0
No logging at all
.TP
.B 1
Errors, usually leading to immediate termination
.TP
.B 2
Warnings, usually affecting BuGLe functionality
.TP
.B 3
Notices, usually OpenGL errors or undefined behaviour
.TP
.B 4
Info from filtersets that generate logs, such as
.BR bugle-trace (3).
.TP
.B 5
Debugging messages
.RE
.TP
.B stderr_level
Similar to
.BR file_level ,
but for logging to standard error. The default is 4 for a file and 3 for
standard error.
.TP
.B format
This optional string overrides the default log format. The following
printf-style escapes are recognised:
.RS
.TP
.B %l
log level
.TP
.B %f
filter-set
.TP
.B %e
event
.TP
.B %m
log message
.TP
.B %p
process ID
.TP
.B %t
thread ID (from
.BR pthread_self (3))
.TP
.B %%
a literal %
.RE
.SH AUTHOR
.B gldb
and the
.B bugle
library are written and maintained by Bruce Merry
<bmerry@users.sourceforge.net>.
.SH SEE ALSO
.BR bugle (3)