Re: suggested addition to 'date'

Sam Leffler wrote:

>Julian Elischer wrote:
>  
>
>>At various times I've wanted to add timestamps to logfiles as they are
>>generated..
>>
>>usually this has involved perl or something to do it.
>>
>>finally I broke down and just added  a small bit to date(1)
>>
>>the -s option tells date to add a timestamp on the front of every line
>>read in through stdin
>>and put it out through stdout.   teh format of the datestamp is governed
>>exactly as usual so:
>>
>>%ls | ./date -s +"%+: "
>>Fri Aug 11 19:53:34 PDT 2006: CVS
>>Fri Aug 11 19:53:34 PDT 2006: Makefile
>>Fri Aug 11 19:53:34 PDT 2006: date
>>Fri Aug 11 19:53:34 PDT 2006: date.1
>>Fri Aug 11 19:53:34 PDT 2006: date.1.gz
>>Fri Aug 11 19:53:34 PDT 2006: date.c
>>Fri Aug 11 19:53:34 PDT 2006: date.o
>>Fri Aug 11 19:53:34 PDT 2006: extern.h
>>Fri Aug 11 19:53:34 PDT 2006: netdate.c
>>Fri Aug 11 19:53:34 PDT 2006: netdate.o
>>Fri Aug 11 19:53:34 PDT 2006: vary.c
>>Fri Aug 11 19:53:34 PDT 2006: vary.h
>>Fri Aug 11 19:53:34 PDT 2006: vary.o
>>%ls | ./date -s +"%s: "
>>1155351474: CVS
>>1155351474: Makefile
>>1155351474: date
>>1155351474: date.1
>>1155351474: date.1.gz
>>1155351474: date.c
>>1155351474: date.o
>>1155351474: extern.h
>>1155351474: netdate.c
>>1155351474: netdate.o
>>1155351474: vary.c
>>1155351474: vary.h
>>1155351474: vary.o
>>%
>>I attach the diff.
>>I'm sure that someone who is a more competent practicioner of userland C
>>programming
>>can probably clean this up abit.
>>
>>do people think this is a worthwhile addition?
>>
>>An easy to imagine use for this is to add it in the makefile for /usr so
>>that "make buildworld" datestamped its output
>>(for example).
>>
>>it makes it easy to timestamp output from a console logger for example:
>>    
>>
>
>pbj% ls | sed -e "s/^/`date +'%+: '`/"
>Fri Aug 11 20:18:05 PDT 2006: Desktop
>Fri Aug 11 20:18:05 PDT 2006: Desktop DB
>Fri Aug 11 20:18:05 PDT 2006: Desktop DF
>Fri Aug 11 20:18:05 PDT 2006: Documents
>Fri Aug 11 20:18:05 PDT 2006: Library
>Fri Aug 11 20:18:05 PDT 2006: Movies
>	...
>  
>

You can do that in shell too but it's running date once for every line 
which probably includes an instance of shell too
so it's hardly light weight when you consider that it might have to deal 
with bursts of thousands of line sper second
occasionally.

This is the sort of hack I was doing before..

In my opinion adding the ability to use date as a filter is an extension 
of the unix philosopy.
it prints dates and it does it well. Let it print dates onto a stream ;-)