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awk "if not exists in (cat filename)"

awk "if not exists in (cat filename)"

awk "if not exists in (cat filename)"

i don't know if i am blaming me with my question, but i have the following "problem".
File one looks like:
gdsfa9078470840 uiupqepquwerop8973070780570

file two is a list with numbers.
334 ...

What i need to do is, to check every line in file one, if on Position 10-12, there is one of the numbers, listed in file 2. Then this line should be ignored.
The rest of the lines schould be wrinten in a new file output.txt

Maybe i am trying it with the wrong tool i don't know...

I would apreciate if someone could give me an advice..


RE: awk "if not exists in (cat filename)"

THANK YOU!!!! Yes it works!

RE: awk "if not exists in (cat filename)"

Great, you have your answer. To keep your mind opened, I give you two other ways:


sed 's/.*/.........&/' pattern.txt|grep -vf - filepattern.txt


sed 's/.*/.\\{9\\}&/' pattern.txt|grep -vf - filepattern.txt

Where filepattern.txt is the first file you described, and pattern.txt, the second.

RE: awk "if not exists in (cat filename)"



sed 's/.*/^.........&/' pattern.txt|grep -vf - filepattern.txt


sed 's/.*/^.\\{9\\}&/' pattern.txt|grep -vf - filepattern.txt

RE: awk "if not exists in (cat filename)"

Hi FlorianAwk.. thanks a lot for your solution too! REGEXs are impressing me everytime :)

@PHV for me to understand it better.. what exactly is the funktion of
I can imagine what, but i could not find an examble which i can say i could understand to 100% and be absolutely sure about the function of it..

I hope you have 5 min to explain it.

RE: awk "if not exists in (cat filename)"

n contains the entries from filetwo=$1..

and the second "n" in  (substr($0,10,3) in n) reffers to fileone

ok i have it..


RE: awk "if not exists in (cat filename)"

is it possible to put this in an IF request?

the whole thing changed a little bit, and i have now to check, if the current line from fileone, whichis in access from awk, if the substring has a value which exists in filetwo, then i have to do something....

so i tried over ...

CODE --> bash

cat fileone | awk 'val=substring($0.10,3); if (grep -q val "filetwo"){printf(val"\n")}' 

so i thougt if the IF request is true, i will get an output. But i get ALL as result. No filtering.
it don't works...

I would apreciate every idea!


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