Time Stamp

Settings -> Preferences -> Text box - Time Stamps
(/set stamp_text_format)

eg.: Time stamp format: [%H:%M:%S]
Will show time stamp as: [23:04:15]

%H = Hour in 24-hour format (00 - 23).
%M = Minute as decimal number (00 - 59).
%S = Second as decimal number (00 - 59).
 

Logging

Settings -> Preferences -> Logging - Logging
(/set irc_logmask)

eg.: Log filename: /home/username/.xchat2/xchatlogs/%n-%c-%b-%Y.txt
Will name your logfiles as: Freenode-#xchat-Apr-2008.txt

%n = Network.
%c = Channel.
%b = Abbreviated Month name.
%Y = Year with century, as decimal number.
 

Timestamps in logs

Settings -> Preferences -> Logging - Time Stamps
(/set stamp_log_format)

eg.: Log timestamp format: [%b %d/%H:%M:%S]
Will show timestamp in your logs as: [Apr 24/21:19:59]

%b = Abbreviated month name.
%d = Day of month as decimal number (01 - 31).
%H = Hour in 24-hour format (00 - 23).
%M = Minute as decimal number (00 - 59).
%S = Second as decimal number (00 - 59).
 

%a

Abbreviated weekday name.
 

%A

Full weekday name.
 

%b

Abbreviated month name.
 

%B

Full month name.
 

%C

The century number (year/100) as a 2-digit integer.
 

%d

Day of month as decimal number (01 - 31).
 

%D

Equivalent to %m/%d/%y.
 

%e

Like %d, the day of the month as a decimal number, but a leading zero is replaced by a space.
 

%F

Equivalent to %Y-%m-%d (the ISO 8601 date format).
 

%H

Hour in 24-hour format (00 - 23).
 

%I

Hour in 12-hour format (01 - 12).
 

%j

Day of year as decimal number (001 - 366).
 

%k

The hour (24-hour clock) as a decimal number (range 0 to 23); single digits are preceded by a blank (See also %H).
 

%l

The hour (12-hour clock) as a decimal number (range 1 to 12); single digits are preceded by a blank (See also %I).
 

%m

Month as decimal number (01 - 12).
 

%M

Minute as decimal number (00 - 59).
 

%p

Current locale's A.M./P.M. indicator for 12-hour clock.
 

%P

Like %p but in lowercase: "am" or "pm".
 

%S

Second as decimal number (00 - 59).
 

%U

Week of year as decimal number, with Sunday as first day of week (00 - 53).
 

%w

Weekday as decimal number (0 - 6; Sunday is 0).
 

%W

Week of year as decimal number, with Monday as first day of week (00 - 53).
 

%x

Date representation for current locale.
 

%X

Time representation for current locale.
 

%y

Year without century, as decimal number (00 - 99).
 

%Y

Year with century, as decimal number.
 

%z - %Z

Either the time-zone name or time zone abbreviation, depending on registry settings; no characters if time zone is unknown.