delete line from pattern matching

anyera has asked for the wisdom of the Perl Monks concerning the following question:

line =08 * * 3 /data/reports/bin/xyz.ksh -o customreports.com -f abc.sql -m xyz.com -c -g

file:- abc.crontab

08 * * 3 /data/reports/bin/xyz.ksh -o customreports.com -f abc.sql -m xyz.com -c -g

06 * * 3 /data/reports/bin/xyz.ksh -o customreports.com -f abc.sql -m xyz.com -c -g

I have searched the line using following command

grep -F "08 * * 3" abc.crontab | grep "abc.sql"

I get the first line from file,I want to delete the exact matching line from abc.crontab

If I use sed -e '/abc.sql /d' abc.crontab/

$cmdperl ="perl -i -nle 'print if !/abc.sql/' abc.crontab ";

then both the lines get deleted from file. Please suggest me the solution.

Comment on delete line from pattern matching

Replies are listed 'Best First'.
Re: delete line from pattern matching by davido (Cardinal) on Jun 18, 2012 at 16:49 UTC
In an effort to minimize the changes to your existing strategy: `$cmdperl = "perl -i -nle 'print if !/abc.sql/ \|\| $found++;' abc.cronta +b";` [download] The first time that `/abc.sql/` matches, the `\|\|` logical short circuit will evaluate `$found` to be 'false', and thus no '`print` will take place. However, because the `$found++` expression was evaluated, `$found` will be incremented, making it "true". The next time `/abc.sql/` matches, the `\|\|` logical short circuit will evaluate `$found` as true, and will `print`. So the first time the "drop line" is found it gets skipped, and all other lines get printed. There may be more elegant (a Perl-afficionado's eyes) pure-Perl solutions, but sometimes the best solution is to just fix the line that needs fixing, and move on. ;) By the way: This is untested, so change the `-i` flag to `-i.bak` until you're sure it does what you want. Dave	[reply] [d/l] [select]
Re: delete line from pattern matching by 7stud (Deacon) on Jun 18, 2012 at 19:54 UTC
I have searched the line using following command: `grep -F "08 * * 3" abc.crontab \| grep "abc.sql"` I get the first line from file,I want to delete the exact matching line from abc.crontab How about this: `perl -i -nle 'print if !(/08 [] [] 3/ and /abc.sql/)' abc.crontab`	[reply] [d/l] [select]