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sed discard chars after last _

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# 1  
Old 05-12-2010
sed discard chars after last _
Hi,

I'd get fields like
Code:
 
unix_linux_form_yyyyddmmhhmi.file.txt
shell_programming_and_scripting.txt

so on...

and want them as below
Code:
 
unix_linux_form
shell_programming_and

I could remove everything after a '.' as below
Code:
echo $field | sed 's/\..*//'

but how to remove characters after the last '_' (as no. of _ might vary and also there is no definite pattern).
-dips
# 2  
Old 05-12-2010
try
Code:
echo $var |awk -F_ 'BEGIN{OFS="_"}{$NF=""}1'|sed 's{_${{'

# 3  
Old 05-12-2010
Thanks posix! It works.
But can you please explain the awk command?

-dips
# 4  
Old 05-12-2010
Smilie The bash way:
Code:
echo ${var%_*}

# 5  
Old 05-12-2010
Or with sed:
Code:
sed 's/\(.*\)_.*/\1/' file

# 6  
Old 05-12-2010
You can use:

Code:
cat file1|awk -F_ 'BEGIN{OFS="_"}{$NF=""}1'|sed 's/_$//'


Moderator's Comments:
Mod Comment Please use code tags!
Last edited by Franklin52; 05-12-2010 at 03:44 AM..
# 7  
Old 05-12-2010
Quote:
Originally Posted by RahulJoshi
You can use:

Code:
cat file1|awk -F_ 'BEGIN{OFS="_"}{$NF=""}1'|sed 's/_$//'

Are you going for the Useless Use of Cat Award?
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