sed command to replace if( with if (

Question

I want to run a sed command : sed command to replace if( with if (

My command looks like this:

sed 's/if(/if ( /g' file1.c >file1.c

where file1.c contains the string that needs to be replaced.

Problem is file contents gets cleared and no changes are reflected.

You cannot redirect to the same file: it gets truncated first and then evaluated. Instead, use `sed -i '...' file` to do in-place replacement, or just redirect to another file. — fedorqui, May 14 '14 at 11:48

score 0 · Answer 1 · edited May 14 '14 at 12:43

0

Use this:

sed -re 's/if(/if ( /g'

edited May 14 '14 at 12:43

Undo

answered May 14 '14 at 12:01

angel

No. Current command works, it is just a problem in the (re-)direction. – fedorqui May 14 '14 at 12:08

score 0 · Accepted Answer · edited May 14 '14 at 14:25

0

You can try two different approaches.

If you want to update existing file:

sed -i 's/if(/if ( /g' file1.c

If you want to store the modified file in another file:

sed 's/if(/if ( /g' file1.c > file2.c

edited May 14 '14 at 14:25

fedorqui

answered May 14 '14 at 12:13

angel

Solutions do not make sense. Also, why posting another answer? – fedorqui May 14 '14 at 13:20
I proposed you 2 differents way to edit you file content... 1st way is to edit existing. (overwrite) 2nd way crete a new file with the edit. – angel May 14 '14 at 13:40
First one is not editing, will just show in the screen. Second has an unnecessary pipe, should just be `sed '...' file1.c > file2.c` – fedorqui May 14 '14 at 13:56
your're right ! sorry :-( – angel May 14 '14 at 14:22

2 Answers2