How to grep file paths out of a text file

grepsedtext processing

I have a file that has a list of paths like so:

"1"       "/user/bin/share"
"2"       "/home/user/.local"
"3"       "/root/"

Is there a way to extract just the paths? I dont want the numbers or quotation marks. How can I sed or grep the paths out of the file? What regex would be required for such a task?

Best Answer

If all the paths start with /, you could just match / followed by a sequence of non-" characters:

$ grep -o '/[^"]*' file
/user/bin/share
/home/user/.local
/root/

Alternatively, for a more structured approach, use awk to strip quotes from and print just the second field:

awk '{gsub(/"/,"",$2); print $2}' file

Related Solutions

Grep – How to Find Text Between Two Strings

With grep -P/pcregrep, using a positive look-behind and a positive look-ahead:

grep -P -o '(?<=STRING1).*?(?=STRING2)' infile

in your case replace STRING1 with filename- and STRING2 with \.tar\.gz

If you don't have access to pcregrep and/or if your grep doesn't support -P you can do this with your favourite text processing tool. Here's a portable way with ed that gives you the same output:

ed -s infile <<\IN
g/STRING1/s//\ 
&/g
v/STRING1.*STRING2/d
,s/STRING1//
,s/STRING2.*//
,p
IN

How it works: a newline is prepended to each STRING1 occurrence (so now there's at most one occurrence per line) then all lines not matching STRING1.*STRING2 are deleted; on the remaining ones we only keep what's between STRING1 and STRING2 and print the result.

Find all users home directories listed using grep from /etc/passwd

Grep is really not the tool for parsing out data this way; grep is more for pattern matching and you're trying to do text-processing. You would want to use awk.

awk -F":" '$7 == "/bin/false" {print "User: "$1 "Home Dir: "$6}' /etc/passwd

awk – The command
-F":" – Sets the data delimiter to :
$7 == "/bin/false" – Checks if the 7th data column is /bin/false
{print "User: "$1 "Home Dir: "$6}' – Says to print the first column and sixth column in the specified format.
/etc/passwd – Is the file we're processing

Best Answer

Related Solutions

Grep – How to Find Text Between Two Strings

Find all users home directories listed using grep from /etc/passwd

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