linux/solaris insert date & time at the beginning of each line in file

Question

I want to add date & time at the begging of each line in some file

I used sed in order to add the date & time before each line in file

please advice what I need to update in my sed in order to support this action ,

I can accept other solution with awk or perl one liner etc ...

# date="[`date +%d"/"%b"/"%G"-"%T`]"
# echo $date
[21/Feb/2013-14:07:58]
#  sed "s/^/$date /" file     
sed: command garbled: s/^/[21/Feb/2013-14:07:58] /

example

file before edit

 param1=3478374
 param2=34128374
 param3=34783743

file after edit

 [21/Feb/2013-14:07:58] param1=3478374
 [21/Feb/2013-14:07:58] param2=34128374
 [21/Feb/2013-14:07:58] param3=34783743

score 3 · Accepted Answer · answered Feb 21 '13 at 13:19

or use another separator like "|", i tried it on mac.

$ date="[`date +%d"/"%b"/"%G"-"%T`]"
$ echo $date
[21/Feb/2013-21:17:22]

$ cat /tmp/a
param1=3478374
param2=34128374
param3=34783743

$ sed "s|^|$date  |g" /tmp/a 
[21/Feb/2013-21:14:15]  param1=3478374
[21/Feb/2013-21:14:15]  param2=34128374
[21/Feb/2013-21:14:15]  param3=34783743

score 2 · Answer 2 · answered Feb 21 '13 at 13:08

There are too many slashes in that sed command. The ones in your $date variable need to be escaped.

This is what I get (which is a somewhat more useful error message):

> echo foo | sed "s/^/[21/Feb/2013-14:07:58] /"
sed: -e expression #1, char 9: unknown option to `s'
> echo foo | sed "s/^/[21\/Feb\/2013-14:07:58] /"
[21/Feb/2013-14:07:58] foo

Escaped:

date="[`date +%d"\/"%b"\/"%G"-"%T`]"

You may need to double-escape your variable if single-escaping is not enough because the escaping may be removed when the variable is dereferenced:

date="[`date +%d"\\/"%b"\\/"%G"-"%T`]"

linux/solaris insert date & time at the beginning of each line in file

2 Answers2