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Replacing Awk with One-liner Perl

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# 1  
Old 12-23-2011
Replacing Awk with One-liner Perl
can someone help me translate the following command, from:

Code:
/usr/bin/awk "/^$TOFDAYM  $TOFDAYD /,0" $LOGFILE

to something like

Code:
perl -e .....

basically, i want to use perl to do awk functions within a shell script. i want to do the above awk, using perl.

any suggestions?
# 2  
Old 12-23-2011
Code:
 
perl -lane 'BEGIN{$f=0} $a=$_;if ($a=~/^$TOFDAYM  $TOFDAYD/ && ($f eq 0)){print $a; $f=$f+1;}elsif ($f gt 0){print $a;}' $LOGFILE

---------- Post updated at 10:27 AM ---------- Previous update was at 10:22 AM ----------

Code:
perl -lane 'BEGIN{$f=0} if ($_=~/^$TOFDAYM  $TOFDAYD/ && $f eq 0){print $_; $f++}elsif ($f gt 0){print $_}' $LOGFILE

# 3  
Old 12-23-2011
1. I don't think your awk one-liner would work as you're not passing $TOFDAYM and $TOFDAYD from shell to awk.
2. When you say 0 at the end, it would print the line regardless of whether the condition is met or not.

What is your requirement exactly? Please provide a sample input and sample output. It would help us to build a perl one-liner.
# 4  
Old 12-23-2011
Quote:
Originally Posted by balajesuri
1. I don't think your awk one-liner would work as you're not passing $TOFDAYM and $TOFDAYD from shell to awk.
2. When you say 0 at the end, it would print the line regardless of whether the condition is met or not.

What is your requirement exactly? Please provide a sample input and sample output. It would help us to build a perl one-liner.

thank you for your response.

this is to be used on a log file. i.e., the /var/log/messages file.

what i want to do is search for a date, like "Dec 23". such a date would of course be the first entry in the lines of the log. hence the need for the "^".

but here's what i need to do. i need to search for a date in a log file, and when that date is found, i need to spit out to screen every line/record that comes after that date including the first matching line.

the above perl one liner provided by itkamaraj didn't seem to work. it just hung there and didn't do anything. anymore suggestions?

thanks a lot guys
# 5  
Old 12-23-2011
Are you looking for something like this?

Code:
user@ubuntu:~/programs$ cat input
This is the first line of log file
Dec 23
This is the third line
This is the fourth line

Code:
user@ubuntu:~/programs$ perl -ne '(/^Dec 23/)&&($p=1);($p==1)&&(print)' input
Dec 23
This is the third line
This is the fourth line

# 6  
Old 12-23-2011
Quote:
Originally Posted by balajesuri
Are you looking for something like this?

Code:
user@ubuntu:~/programs$ cat input
This is the first line of log file
Dec 23
This is the third line
This is the fourth line

Code:
user@ubuntu:~/programs$ perl -ne '(/^Dec 23/)&&($p=1);($p==1)&&(print)' input
Dec 23
This is the third line
This is the fourth line

The Log looks likes something like this:

Code:
Dec 23 20:54:84 This is the first line of the log.  This is great. I am so happy.
Dec 23 20:54:14 This is the sec line of the log.  This is great. I am so happy.
Dec 23 20:54:14 This is the thir line of the log.  This is great. I am so happy.
Dec 23 20:54:14 This is the fou line of the log.  This is great. I am so happy.
Dec 23 20:54:14 This is the fifth line of the log.  This is great. I am so happy.

# 7  
Old 12-23-2011
Ok.. What happened? Isn't the perl one-liner working?
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