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Help with deleting lines and saving them

 
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# 1  
Old 05-09-2012
Help with deleting lines and saving them
I have a directory question where I ask the user which entry he wants to delete...

Code:
echo  "Which entry?"
read entry
sed '/^'$entry'/d' file

This code does in fact delete that particular entry...
HOWEVER, when I go to inquire about that same entry, it still populates like it was never deleted. How can I fix this?

Moderator's Comments:
Mod Comment If you continue to ignore requests for code tags and don't read your related PMs, you will soon be banned cause of that; up to you.
Last edited by zaxxon; 05-09-2012 at 09:39 AM..
# 2  
Old 05-09-2012
Use option -i for in-place editing of files.

Code:
sed -i '/^'$entry'/d' file

# 3  
Old 05-09-2012
I'm guessing he wants to check the file for entry before sedin' it.

Something like :
Code:
echo  "Which entry?"
read ENTRY
grep -q "^$ENTRY" file && sed "/^$ENTRY/d" file || printf "Entry $ENTRY not found \n"

# 4  
Old 05-09-2012
It says there is no -q option for the grep command. I am using bash shell if that matters. Is there some kind of if statement I can use for checking the file for the entry??
# 5  
Old 05-10-2012
-q is for silent (don't print anything)

Use it without, if your grep doesn't have it.
 
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