file content

elainelaw · 07-23-2009, 04:45 AM

I have a file , the file content is as below

$vi file
xxxxxaaa.txt
bbb.txt
xxxxxccc.txt
xxxxxddd.txt
eee.txt
xxxxxfff.txt

if I want to extract some content from this file , the condition is

1. the files are begins with xxxxx
2. remove xxxxx from the file name

so that the output should be

my desired output
============
aaa.txt
ccc.txt
ddd.txt
fff.txt

can adivse what can i do ? thx

ygdrazil · 07-23-2009, 04:54 AM

To get the lines with xxxxx:
grep "\<[xxxxx].*" file

How to emit the x's in the direct output i don't know.

ygg

karamarisan · 07-23-2009, 04:57 AM

If it's a fixed pattern, pipe the output of that grep to sed with this:

Code:

grep xxxxx | sed 's/xxxxx//'

If you need more than that, it may help to show us exactly what you're working on.

colucix · 07-23-2009, 04:58 AM

Code:

sed 's/^xxxxx//g' file

use -i option if you want to actually modify the file.

A little advice, if I can: you should consider to read some good manuals about bash, sed and awk programming, since your questions (as per your previous threads) are really basic and you should put a very little effort to solve the issues. Here are some good readings to start with:
http://www.tldp.org/LDP/Bash-Beginne...tml/index.html
http://www.grymoire.com/Unix/Sed.html
http://www.gnu.org/software/gawk/manual/
http://www.tldp.org/LDP/abs/html/index.html (keep this as a reference guide)

Tinkster · 07-23-2009, 05:17 AM

If I understand the OP correctly (which I most likely don't)
the sed line should be

Code:

sed -n '/^xxxx/ s/^xxxxx//gp' file
aaa.txt
ccc.txt
ddd.txt
fff.txt

Cheers,
Tink

elainelaw · 07-23-2009, 05:25 AM

thx replies ,

I tried all suggestion ,but the output is as below

aaa.txt
bbb.txt
ccc.txt
ddd.txt
eee.txt
fff.txt

but it seems not the output that I desired , can advise how to adjust to output my desired result ? thx

karamarisan · 07-23-2009, 05:28 AM

Quote:

Originally Posted by elainelaw

but the output is as below

The output of what?

elainelaw · 07-23-2009, 05:36 AM

deleted

pixellany · 07-23-2009, 05:43 AM

The solution offered by Tinkster should have worked. Note the following variants:

Code:

sed -n '/^xxxx/ s/^xxxxx//gp' filename   ## Writes the output to the screen

sed -i -n '/^xxxx/ s/^xxxxx//gp' filename   ## Modifies filename in place

sed -n '/^xxxx/ s/^xxxxx//gp' filename > newfilename   ## Writes the output to a new file ("newfilename")

Did you look at the references that were suyggested?

elainelaw · 07-23-2009, 05:45 AM

Quote:

Originally Posted by karamarisan

The output of what?

it works , I would like to ask if it is not xxxxx , it is some special characters eg. ? / ! , what can i do ? thx

pixellany · 07-23-2009, 06:05 AM

elainelaw;

You are still not telling us which answer is working!! People have given you several suggestions---you need to tell us what you are referring to......

The general rule for using special characters in something like SED is to "escape" them using "\". Here is just one example:

Code:

Input file:
xxxxxaaa.txt
bbb.txt
xxxxxccc.txt
xxxxxddd.txt
eee.txt
/xxxxxfff.txt

sed -n /^\/xxxxx/s/\/xxxxx//gp filename

At the Grymoire site suggested earlier, there is a section on Regular Expressions--this and the SED tutorial will give you more details on escaping.

elainelaw · 07-23-2009, 06:15 AM

Quote:

Originally Posted by pixellany

elainelaw;

You are still not telling us which answer is working!! People have given you several suggestions---you need to tell us what you are referring to......

The general rule for using special characters in something like SED is to "escape" them using "\". Here is just one example:

Code:

Input file:
xxxxxaaa.txt
bbb.txt
xxxxxccc.txt
xxxxxddd.txt
eee.txt
/xxxxxfff.txt

sed -n /^\/xxxxx/s/\/xxxxx//gp filename

At the Grymoire site suggested earlier, there is a section on Regular Expressions--this and the SED tutorial will give you more details on escaping.

thx

your program works for me . really thx a lot.