[CTX] [ALL] LogFilename and Aging

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LogFilename and dirPath Substitution for Aging

If the pattern "[date+format]" is included in the file name, the format string is evaluated by strftime(3) compatible function with the current time, and will be substituted with the evaluated value. This means that a log directory (or file) specified will be divided into a granularity of specified time period, thus it is aged. Formats to represent typical time periods are as follows:
%Y -- year (like 2000)
%y -- year without century [00-99]
%m -- month number [01-12]
%d -- day of month [01-31]
%W -- week number of year [00-53]
%w -- weekday number [0-6, Sunday=0]
%H -- hour [00-23]


Example: aging a log file day by day and rotate by a month

LOGFILE='${PORT}[date+.%d]'

Example: make log directory hierarchical by date

LOGDIR='log[date+/aged/%y/%m/%d]'

The latest LOGFILE will be pointed with another file name (hard link to it) which name is made by omitting "[date+format]" parts from LOGFILE specification. For example, by the LOGFILE specification in the above example, logfile will be named like "log/aged/00/12/31/80.http" while the latest one is given another name "log/80.http".

Another pattern for aging is "[start+format]" which will be evaluated in the same way with "date+" except that it will be substituted by the time when the DeleGate started (or restarted by SIGHUP or specified TIMEOUT=restart).

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