Replace date in a parameter file with system date

Question

In my Unix AIX I need to replace the date in a parameter file with system date using a shell script that will run post session from PowerCenter.

I can use SED to replace a string variable but running into issue using date.

I have tried using commas instead of slashes as delimiters. The contents of the test file looks like this:

$$TESTFIELD=12/29/2016 14:57:51

The sed command I felt should work was:

sed -e "s,^\($$TESTFIELD=\).*,\1'date +"%D %T"'," testfile.txt > tmp.$$

After which I would move the tmp.$$ to testfile.txt but the results threw the following error:

sed: 0602-404 Function s,^\(14680298TESTFIELD=\).*,\1'date +%D cannot be parsed.

note that you are using double quotes, so `sed -e "s..."` expands `$$TESTFIELD` to its value. — fedorqui, Jan 18 '17 at 15:15
You may want to have a look to [How to change date format in sed?](http://stackoverflow.com/a/34080390/1983854) also, to see how to execute an external command from within `sed`. Basically, you need to use the `-e` flag. — fedorqui, Jan 18 '17 at 15:18
Maybe: `Now=$(date +"%D %T"); sed "s,=.*$,=$Now," testfile.txt >>tmp.$$` — Lorinczy Zsigmond, Jan 18 '17 at 17:34

hek2mgl · Accepted Answer · 2017-01-18T18:08:03.940

2

You need to use single quotes or escape the $ in the sed command. Otherwise the shell would expand $TESTFIELD. I recommend the first in this case:

sed -e 's,^\($$TESTFIELD=\).*,\1'\''date +"%D %T"'\'','

Your question is quite unclear. If you want to replace the datetime in the file by the current datetime, use:

sed -e 's,^\($$TESTFIELD=\).*,\1'"$(date +"%D %T")"','

edited Jan 18 '17 at 18:08

answered Jan 18 '17 at 15:18

hek2mgl

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That approach doesn't insert the current date/time but actually inserts dat+"%D %T": $$TESTFIELD='date +"%D %T"' – Thomas J. Huber Jan 18 '17 at 17:26
Reading your question, it looks like you want that – hek2mgl Jan 18 '17 at 17:30
I apologize, I need the result to be 01/18/2017 12:34:30 or whatever the current date time is. – Thomas J. Huber Jan 18 '17 at 17:34
The results are now: $$TESTFIELD='01/18/17 12:36:50' I tried to remove a couple of the quotes to remove the quotes in the results. I can probably do this in PowerCenter later if its not easy here. – Thomas J. Huber Jan 18 '17 at 17:42
Removed them. Actually that was pretty simply – hek2mgl Jan 18 '17 at 18:08
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Perfect. Thank you very much. – Thomas J. Huber Jan 18 '17 at 18:16

score 0 · Answer 2 · answered Jan 18 '17 at 18:19

0

sed -e 's,^\($$TESTFIELD=\).*,\1'"$(date +"%D %T")"','

This worked perfectly. Results: $$TESTFIELD=01/18/17 13:14:59

answered Jan 18 '17 at 18:19

Thomas J. Huber

51
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Replace date in a parameter file with system date

2 Answers2