Shell Programming and Scripting

hi there ,

i m new to unix , i d like to ask how can a get only even numbered lines matches with the word i search from txt file

for example :



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i want to grep (or any other commands ) the evenly number lines such as ;
.
.
.

3496:1.E.3. If an individual Project Gutenberg-tm electronic work is posted
3494:1.E.9.
3562:1.E.9. If you wish to charge a fee or distribute a Project Gutenberg-tm
.
.
.

i hope i m clear enough i tried many regular expressions but didn t work

THE PROBLEM IS PUNCTUATION ( : ) i believe bcus it reads them all as one string that makes it hard to seperate! , there might be other numbers in the line !

i don t know why this doesn t work grep -n '[0-9]*[08]*' list.txt

I'm not 100% sure what you're doing in that regex but remember that * has a slightly different meaning in a regex than it does in shell globbing. In a shell, * means "match zero or more of any character". In a regex it means "match zero or more of the previous character". So [0-8]* tells it to match zero or more characters in the set 0-8. Also, in a regex, . is a special character meaning "any character".

So I think you could do:

Code:

grep "...[02468]" filename

which will match anything for the first three chars, then only even numbers for the last digit.

i didn't completely understand what you mean. If you just want to get the lines with even number lines, you could try this:

Code:

kent$ seq 10|sed -n 'n;p;'
2
4
6
8
10

if this is what you want, you could

Code:

 sed -n 'n;p;' yourfile

ok but point is "i need to get evenly line numbers"

Code:

grep "...[02468]" filename

same number mixed string combination can be placed any where in any line

3461:1.D. The copyright laws of the place where you are located also govern

what i need is get the line number 3461 from a line only if it s an even number!

---------- Post updated at 11:59 AM ---------- Previous update was at 11:56 AM ----------

[/CODE]if this is what you want, you could

Code:

 sed -n 'n;p;' yourfile

[/QUOTE]

is exactly wht i need , thank u very much bro.

Code:

sed -n '/^[0-9]*[02468]:/p' myFile

deleted since misunderstood the requirement.

this can be simplified:

Code:

nawk -F: '!$1%2' myFile