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Flasher

Member

From: Bavaria / Germany

Registered: 2005-04-24

Posts: 126

How to cut Strings found by grep?

Hello,

I have a simple problem

I'm searching after the pkgver in the PKGBUILD file.
No problem: cat PKGBUILD | grep 'pkgver='

For example I get: 'pkgver=2.6.23.8'

But I only want the string '2.6.23.8'

I tested tail, head, basename   and sed (complex) but I couldn't find any solution.

I think there must be a simple solution

Thanks for help!

Best regards,

Flasher

MrWeatherbee

Member

Registered: 2007-08-01

Posts: 277

Re: How to cut Strings found by grep?

I think there must be a simple solution

A few ways. Try this:

echo pkgver=2.6.23.8 | cut -d= -f2

nj

Member

Registered: 2007-04-06

Posts: 93

Re: How to cut Strings found by grep?

You can use cut to break it at the equals sign and then take the second field.

cat PKGBUILD | grep pkgver= | cut -d = -f 2

byte

Member

From: Düsseldorf (DE)

Registered: 2006-05-01

Posts: 2,046

Re: How to cut Strings found by grep?

grep ^pkgver= PKGBUILD | cut -d= -f2

awk -F = '/^pkgver=/ { print $2 };' PKGBUILD

---

1000

tomk

Forum Fellow

From: Ireland

Registered: 2004-07-21

Posts: 9,839

Re: How to cut Strings found by grep?

Offtopic, but I have to point out the useless use of cat - do this instead:

grep pkgver= PKGBUILD | ...

MrWeatherbee

Member

Registered: 2007-08-01

Posts: 277

Re: How to cut Strings found by grep?

Offtopic, but I have to point out the useless use of cat - do this instead:

grep pkgver= PKGBUILD | ...

Here ya go:

http://sial.org/howto/shell/useless-cat/

Cerebral

Forum Fellow

From: Waterloo, ON, CA

Registered: 2005-04-08

Posts: 3,108

Website

Re: How to cut Strings found by grep?

One-liner in sed (don't even need to use grep!):

$ sed -n "/pkgver=/ { s/pkgver=//; p }" PKGBUILD
      ^   ^           ^            ^ Tells sed to print the line
      ^   ^           ^ This part strips out pkgver=
      ^   ^This part does the grep for you
      ^ This part tells sed to print nothing unless told

Last edited by Cerebral (2007-12-03 03:41:13)

Bebo

Member

From: Göteborg, Sweden

Registered: 2006-06-07

Posts: 207

Re: How to cut Strings found by grep?

Another sed version:

sed -n "s/^pkgver=\(.*\)$/\1/p" PKGBUILD

Or you can do

. PKGBUILD

and then just use $pkgver directly

elide

Member

From: Russia

Registered: 2007-12-02

Posts: 40

Re: How to cut Strings found by grep?

Or you can do . PKGBUILD and then just use $pkgver directly

And what about "rm -rf /" somewhere in PKGBUILD ? (;

grep -Po "(?<=^pkgver=)(\d+\.?)+" PKGBUILD

Last edited by elide (2007-12-03 07:48:44)

Cerebral

Forum Fellow

From: Waterloo, ON, CA

Registered: 2005-04-08

Posts: 3,108

Website

Re: How to cut Strings found by grep?

Another sed version:

sed -n "s/^pkgver=\(.*\)$/\1/p" PKGBUILD

Actually, you don't need to bother with storing the result:

sed -n "s/^pkgver=//p" PKGBUILD

works, and is simpler.

Bebo

Member

From: Göteborg, Sweden

Registered: 2006-06-07

Posts: 207

Re: How to cut Strings found by grep?

@Cerebral: Gah, yes, of course I'm usually using sed to a bit more complex patterns, so it didn't strike me that I could do it simpler

Cerebral

Forum Fellow

From: Waterloo, ON, CA

Registered: 2005-04-08

Posts: 3,108

Website

Re: How to cut Strings found by grep?

@Cerebral: Gah, yes, of course I'm usually using sed to a bit more complex patterns, so it didn't strike me that I could do it simpler

lol - same here.  Take a look at my first version - totally more complex than necessary. XD