Update to existing User Tip

Question

This is an update to Date and Time in the Menu Bar (10.3, 10.4) to account for the fact that it is also applicable in 10.5.
In addition it corrects the appearance of 4 horizontal rules in the table which appear because the Jive software is broken if you give it valid HTML. I cannot correct the double spacing in the table, which again is Jive misbehaving with stuff between <pre> and </pre> tags. If you know a way around this, while preserving the single horizontal spacing to keep the table aligned, please modify it accordingly.
Tip follows:
Put the Date in the Menu Bar (10.3, 10.4, 10.5)
To put the date, as well as the time, into the Menu Bar in 10.3 or higher is not the same as in 10.2 and earlier (see the corresponding FAQ for 10.2), and to complicate things further, the format strings used are different. I have run this on an English language version for several years with no apparent problems – others have reported that it works on systems localised to French and German.
This change can only be accomplished using the Terminal application, which you will find in /Applications/Utilities. If you are not comfortable using commands at a command line prompt, do not attempt this change.
Note You should not attempt to type these commands directly, rather use copy and paste to get the commands into a Textedit document (set to Plain Text from the Format menu). Be warned that sometimes copying and pasting from a browser window puts an additional space at the end of a line, so if a command wraps, check that the line has exactly one space where it wraps, and no end-of-line character there. Extra space happens to matter in the "defaults" command because the line wrap tends to occur inside a quoted format string.
The commands below will give, for example, "Thu 2 Dec, 02:15 pm" in the menu bar. If you're in the USA, you might prefer to have the month precede the day, so you would reverse the order of the 'd' and 'MMM' format specifiers. Note that if you put the day-of-week format specifier (EEE) in the string, you will get two days listed if the "Show the day of the week" box is checked in System Preferences > Date & Time > Clock, so un-check that.
Edit the format to your choice (see below for the different codes), then when you are happy with it, paste it into Terminal, and press the return key. If it works, Unix won't tell you – it is very concise. So, one command at a time, and press return after each.
First, take a backup of the existing preference file. Only do this the first time you attempt this – the idea is to keep a copy of the original Apple file. The first command gets to the right directory:
cd ~/Library/Preferences
Then copy the existing file, preserving modification dates, etc:
cp -p .GlobalPreferences.plist .GlobalPreferences.plist.orig
Now set our desired format ALL ONE LINE, please:
defaults write -g AppleICUTimeFormatStrings -dict-add 2 "d MMM, hh':'mm':'ss' 'a"
It is important now to immediately reset the Menu Bar, or our changes will be undone!
killall SystemUIServer
This will cause your Right Hand Menu Bar to disappear and then re-appear in the new format. (This often resets the "Show the day of the week" and "Show seconds" options in "Date & Time", so you may wish to change these). If all looks OK, it is a good idea to save a copy (but you need to have executed the 'cd' command above first):
cp .GlobalPreferences.plist .GlobalPreferences.plist.bak
My experience with this indicates that your changes can be lost if you go into System Preferences > International > Formats and click either of the "Customise" buttons for Date and Time (even if you then "Cancel"). If this happens, it is easy to restore things from this copy:
cd ~/Library/Preferences
cp .GlobalPreferences.plist.bak .GlobalPreferences.plist
killall SystemUIServer
To go back to the Apple default settings, use the same command sequence but replace ".bak" by ".orig".
Formats for Date/Time
<pre> Symbol Meaning Presentation Example
G era designator (Text) AD
y year (Number) 1996
M month in year (Text & Number) July & 07
d day in month (Number) 10
h hour in am/pm (1~12) (Number) 12
H hour in day (0~23) (Number) 0
m minute in hour (Number) 30
s second in minute (Number) 55
S millisecond (Number) 978
E day of week (Text) Tuesday
e day of week/local (1~7) (Number) 2
D day of year (Number) 189
F day of week in month (Number) 2 (2nd Wed in July)
w week in year (Number) 27
W week in month (Number) 2
a am/pm marker (Text) PM
k hour in day (1~24) (Number) 24
K hour in am/pm (0~11) (Number) 0
z time zone (Text) Pacific Standard Time
' escape for text
'' single quote '</pre>
The count of pattern letters determines the format, as follows:
(Text): 4 or more, use full form, (Number): the minimum number of digits. Shorter numbers are zero-padded to this amount (e.g. if "m" produces "6", "mm" produces "06"). Year is handled specially; that is, if the count of 'y' is 2, the Year will be truncated to 2 digits. (e.g., if "yyyy" produces "1997", "yy" produces "97".)
(Text & Number): 3 or over, use text, otherwise use number. (e.g., "M" produces "1", "MM" produces "01", "MMM" produces "Jan", and "MMMM" produces "January".)
This table, with additional notes, can be found at the International Components for Unicode (ICU) User Guide website. Reprinted by permission from International Business Machines Corporation copyright (2000 - 2004).

Answer 1

Put the Date in the Menu Bar (10.3, 10.4, 10.5)
To put the date, as well as the time, into the Menu Bar in 10.3 or higher is not the same as in 10.2 and earlier (see the corresponding FAQ for 10.2), and to complicate things further, the format strings used are different. I have run this on an English language version for several years with no apparent problems – others have reported that it works on systems localised to French and German.
This change can only be accomplished using the Terminal application, which you will find in /Applications/Utilities. If you are not comfortable using commands at a command line prompt, do not attempt this change.
Note You should not attempt to type these commands directly, rather use copy and paste to get the commands into a Textedit document (set to Plain Text from the Format menu). Be warned that sometimes copying and pasting from a browser window puts an additional space at the end of a line, so if a command wraps, check that the line has exactly one space where it wraps, and no end-of-line character there. Extra space happens to matter in the "defaults" command because the line wrap tends to occur inside a quoted format string.
The commands below will give, for example, "Thu 2 Dec, 02:15 pm" in the menu bar. If you're in the USA, you might prefer to have the month precede the day, so you would reverse the order of the 'd' and 'MMM' format specifiers. Note that if you put the day-of-week format specifier (EEE) in the string, you will get two days listed if the "Show the day of the week" box is checked in System Preferences > Date & Time > Clock, so un-check that.
Edit the format to your choice (see below for the different codes), then when you are happy with it, paste it into Terminal, and press the return key. If it works, Unix won't tell you – it is very concise. So, one command at a time, and press return after each.
First, take a backup of the existing preference file. Only do this the first time you attempt this – the idea is to keep a copy of the original Apple file. The first command gets to the right directory:
cd ~/Library/Preferences
Then copy the existing file, preserving modification dates, etc:
cp -p .GlobalPreferences.plist .GlobalPreferences.plist.orig
Now set our desired format ALL ONE LINE, please:
defaults write -g AppleICUTimeFormatStrings -dict-add 2 "d MMM, hh':'mm':'ss' 'a"
It is important now to immediately reset the Menu Bar, or our changes will be undone!
killall SystemUIServer
This will cause your Right Hand Menu Bar to disappear and then re-appear in the new format. (This often resets the "Show the day of the week" and "Show seconds" options in "Date & Time", so you may wish to change these). If all looks OK, it is a good idea to save a copy (but you need to have executed the 'cd' command above first):
cp .GlobalPreferences.plist .GlobalPreferences.plist.bak
My experience with this indicates that your changes can be lost if you go into System Preferences > International > Formats and click either of the "Customise" buttons for Date and Time (even if you then "Cancel"). If this happens, it is easy to restore things from this copy:
cd ~/Library/Preferences
cp .GlobalPreferences.plist.bak .GlobalPreferences.plist
killall SystemUIServer
To go back to the Apple default settings, use the same command sequence but replace ".bak" by ".orig".
Formats for Date/Time
Symbol Meaning Presentation Example
G era designator (Text) AD
y year (Number) 1996
M month in year (Text & Number) July & 07
d day in month (Number) 10
h hour in am/pm (1~12) (Number) 12
H hour in day (0~23) (Number) 0
m minute in hour (Number) 30
s second in minute (Number) 55
S millisecond (Number) 978
E day of week (Text) Tuesday
e day of week/local (1~7) (Number) 2
D day of year (Number) 189
F day of week in month (Number) 2 (2nd Wed in July)
w week in year (Number) 27
W week in month (Number) 2
a am/pm marker (Text) PM
k hour in day (1~24) (Number) 24
K hour in am/pm (0~11) (Number) 0
z time zone (Text) Pacific Standard Time
' escape for text
'' single quote '
The count of pattern letters determines the format, as follows:
(Text): 4 or more, use full form, (Number): the minimum number of digits. Shorter numbers are zero-padded to this amount (e.g. if "m" produces "6", "mm" produces "06"). Year is handled specially; that is, if the count of 'y' is 2, the Year will be truncated to 2 digits. (e.g., if "yyyy" produces "1997", "yy" produces "97".)
(Text & Number): 3 or over, use text, otherwise use number. (e.g., "M" produces "1", "MM" produces "01", "MMM" produces "Jan", and "MMMM" produces "January".)
This table, with additional notes, can be found at the International Components for Unicode (ICU) User Guide website. Reprinted by permission from International Business Machines Corporation copyright (2000 - 2004).