$ echo -e "AsometAhingA\nsomethingA\nASomethiAng"
AsometAhingA
somethingA
ASomethiAng
$ echo -e "AsometAhingA\nsomethingA\nASomethiAng" | sed "s/A//"
sometAhingA
something
SomethiAng
$
I know that sed "s/A//" deletes the first match in every line.
But I want to delete only the first match in a text file or stream.
How can I do this?
Like: sed -i "MAGIC" file.txt
Unfortunately, MAGIC is not a sed command, so you will have to use something else:
sed -i '0,/A/ s///' file.txt
perl -i -pe 'if (!$changed) {s/A// and $changed++;}' file.txt
echo -e "/A/ s///\nwq" | ed file.txt
sed solution, would it still work if "AsometAhingA" was the SECOND or later line, with "A" not happening anywhere prior?
As long as it's GNU sed (which it probably is, since it's Fedora), you should be able to do:
sed '0,/RE/{//d;}' file.txt
If you have a version of sed (non-GNU) that doesn't support 0 as a line address, then you can do this:
sed '/A/{s///;:a;n;ba}' file.txt
It prints each line as is until it finds one with the pattern. Then it deletes the pattern. After that it loops from ba (branch to "a") to :a (label "a") and reads and prints each line without looking for the pattern again.
