printing pattern match and not whole line that matches pattern
 

Hi all.

I've been jumping between the manuals of grep, awk and sed to find a way to print the match of a pattern.
Grep seems able to print the entire line that matches the regular expression, but I want to print only the string that matches the regular expression. I could not find anything in awk or sed manuals.

For example I have a html file that has many links in it. I want to output the location of the links to a plain text file. So I would need to make a regular expression similar to the following:
that matches everything between the quotes of the href.
I could output this to a file and then remove the href part.

What tool should I be using to do this?

Thanks in advance.
Avatar

Hi,

Something like this maybe:

echo '<A HREF="xdpyinfo.1.html">xdpyinfo(1)</A>' | sed 's/.*HREF="\(.*\)".*/\1/'

$ echo '<A HREF="xdpyinfo.1.html">xdpyinfo(1)</A>' | sed 's/.*HREF="\(.*\)".*/\1/'
xdpyinfo.1.html

The \( , \) and \1 are the key. The \1 represents and print that what is found between the \( and \) in the searchstring.

Hope this helps.

That's really cool.

I've gota get into a sed manual/tutorial one of these days :-)

Thanks
Avatar

If your using grep,

grep -o PATTERN

The -o option tells it to output only the matching part of the string. Check out man grep for more info.

Handy one-liners for sed is a nice reference, too. I use it a lot :)

Hi all,

Exactly what I was looking for :-) Only problem: sed prints every line also the ones not mathing. Using -n option suppresses "everything". How can I solve this?

grep -o is nice but doesn't offer the flexibility of using \( \) which allows you to match something bigger but print only part of it.

Thanks in advance!

Dirk

Try

My favorite sed and awk tutorials here: http://www.grymoire.com/Unix/

Hi,

The sed part used is just a search and print, and is indeed done on all lines in a file.

It's not entirely clear to me what you want to match and what you do not want to match, but the following example should get you going again:
Hope this helps.

awk:

Thanks guys! Problem solved: -n in combination with /p. Will have a look at those tutorials... looking good!

Dirk

Similar problems
 

Please help this:

cat aa
<a href=#Say,123> >>Hi<<
<a href=#Say,234> >>Hello<< <a href=#Say,345> >>World<<

123> >
345> >

What is sed or awk command to get like this:
123
234
345

If this work then it is fine but the above is referred.
cat bb
<a href=#Say,123> >>Hi<<
<a href=#Say,234> >>Hello<<

to:
123
234

Using GNU sed

It works
 

It works but then I have another problems so I wrote in awk then. Thanks