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Grep command to search a regular expression in a line an only print the string after the match

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# 1  
Old 08-25-2016
Grep command to search a regular expression in a line an only print the string after the match
Hello,

one step in a shell script i am writing, involves Grep command to search a regular expression in a line an only print the string after the match

an example line is below

Code:
/logs/GRAS/LGT/applogs/lgt-2016-08-24/2016-08-24.8.log.zip:2016-08-24 19:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"

The line can be of variable length but will always have a date time stamp
In above line the timestamp is 2016-08-24 19:12:48,602

i want the output of the command to be
Code:
[ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"

if i run the below command i get the timestamp as output
Code:
echo $line | grep -Eo '[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-3][0-9][ ][0-9][0-9]:[0-9][0-9]:[0-9][0-9],[0-9][0-9][0-9]'

Please suggest.



Moderator's Comments:
Mod Comment Please use CODE tags as required by forum rules!
Last edited by RudiC; 08-25-2016 at 09:11 AM.. Reason: Added CODE tags.
# 2  
Old 08-25-2016
I'm afraid you can't remove the search pattern from grep's result. Either use a different pattern ( e.g. "[ttp" ), or use a different tool ( like sed or awk )
This User Gave Thanks to RudiC For This Post:
Ramneekgupta91
# 3  
Old 08-25-2016
Hello Ramneekgupta91,

Could you please try following(tested with GNU awk).
Code:
awk --re-interval '{match($0,/[0-9]{4}-[0-2][0-9]-[0-9]{2} [0-2][0-9]:[0-5][0-9]:[0-5][0-9].*/);print substr($0,RSTART+24,RLENGTH-24)}'  Input_file
OR
awk --re-interval '{match($0,/[0-9]{4}-[0-2][0-9]-[0-9]{2} [0-2][0-9]:[0-5][0-9]:[0-5][0-9],[0-9]{3} .*/);print substr($0,RSTART+24,RLENGTH-24)}'  Input_file

Output will be as follows.
Code:
[ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"

Adding more solution here.
Code:
awk --re-interval '{sub(/.*[0-9]{4}-[0-2][0-9]-[0-9]{2} [0-2][0-9]:[0-5][0-9]:[0-5][0-9],[0-9]{3} /,X,$0);print}'  Input_file

EDIT: Above solutions may get month more than 12 and time more than 23 too(though one could trust that data will be in correct time format but for exact match and safer side), so edited regex above solutions as follows.
So let's say we have following Input_file:
Code:
/logs/GRAS/LGT/applogs/lgt-2016-08-24/2016-08-24.8.log.zip:2016-08-24 19:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"
/logs/GRAS/LGT/applogs/lgt-2016-08-24/2016-08-24.8.log.zip:2016-18-24 19:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S$$$$$$$"
/logs/GRAS/LGT/applogs/lgt-2016-28-24/2016-08-24.8.log.zip:2016-28-24 59:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"
/logs/GRAS/LGT/applogs/lgt-2016-29-24/2016-08-24.8.log.zip:2016-29-24 59:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"
/logs/GRAS/LGT/applogs/lgt-2016-29-24/2016-08-24.8.log.zip:2016-12-24 59:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"
/logs/GRAS/LGT/applogs/lgt-2016-29-24/2016-08-24.8.log.zip:2016-11-24 59:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"
/logs/GRAS/LGT/applogs/lgt-2016-29-24/2016-08-24.8.log.zip:2016-13-24 59:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"
/logs/GRAS/LGT/applogs/lgt-2016-29-24/2016-08-24.8.log.zip:2016-13-24 79:12:48,602 [ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"

I had put some more scenarios in it by adding 29th month in dates and having more than 59 mins of time too. So following code may resolve those things.
Code:
awk --re-interval '{match($0,/[0-9]{4}-(0[1-9]||1[0-2])-(0[1-9]||1[0-9]||2[0-9]||3[0-1]) ([0-1][1-9]||[0-2][0-3]):[0-5][0-9]:[0-5][0-9],[0-9]{3} .*/);if(substr($0,RSTART+24,RLENGTH-24)){print substr($0,RSTART+24,RLENGTH-24)}}'  Input_file

Output will be as follows.
Code:
[ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"

Because only 1st line meets the criteria so it is printing only that one.

Adding a non-one liner form of solution too now.
Code:
awk --re-interval '{
                        match($0,/[0-9]{4}-(0[1-9]||1[0-2])-(0[1-9]||1[0-9]||2[0-9]||3[0-1]) ([0-1][1-9]||[0-2][0-3]):[0-5][0-9]:[0-5][0-9],[0-9]{3} .*/);
                        if(substr($0,RSTART+24,RLENGTH-24)){
                                                                print substr($0,RSTART+24,RLENGTH-24)
                                                           }
                   }
                  '   Input_file

Thanks,
R. Singh
Last edited by RavinderSingh13; 08-25-2016 at 11:04 AM.. Reason: Added one more solution too here. Improved the REGEX in code and provided to user now.
This User Gave Thanks to RavinderSingh13 For This Post:
Ramneekgupta91
# 4  
Old 08-25-2016
Depending on your shell you could do something like:

Code:
echo ${line/*[0-9][0-9][0-9][0-9]-[0-9][0-9]-[0-3][0-9] [0-9][0-9]:[0-9][0-9]:[0-9][0-9],[0-9][0-9][0-9]/}

# 5  
Old 08-25-2016
Code:
sed -n '/[0-9]\{4\}-[0-9]\{2\}-[0-9]\{2\} [0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\},[0-9]\{3\}/s/.*[0-9]\{4\}-[0-9]\{2\}-[0-9]\{2\} [0-9]\{2\}:[0-9]\{2\}:[0-9]\{2\},[0-9]\{3\} *\(.*\)/\1/p' logfile

# 6  
Old 08-25-2016
rdrtx1's impressing proposal boiled down somewhat:
Code:
sed -n '/^.*[0-9]\{4\}\(-[0-9]\{2\}\)\{2\} \([0-9]\{2\}:\)\{2\}[0-9]\{2\},[0-9]\{3\} \(.*\)/ s//\3/p' file
[ttp-/57.20.70.159:8111-35] ERROR com.lufthansa.lgt.exception.filter.LGTExceptionResolver - The error is : For input string: " S"

or, if your sed offers EREs, try

Code:
sed -En '/^.*[0-9]{4}(-[0-9]{2}){2} ([0-9]{2}:?){3},[0-9]{3} (.*)/ s//\3/p' file

# 7  
Old 08-25-2016
If you put your sed command in a file, it shouldn't be a problem.
Code:
sed -n -f commands.sed

Your commands.sed file would be something like:
/regular expression you are looking for/{
s/xxx/xxx/
p
d
}

The "-n" prevents it from displaying a line without a p command. Change the s command to format it as needed, no problem in using more than one. The p will display it and the d deletes it (perhaps not necessary).

HTH
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