Shell Programming and Scripting

hi ygemici

thanx for ur reply i will try this thing tomorrow

but the thing is in my file $1 exits in my $file and i need to replace it with some variable that's y i added this
but seriously output file is getting generated but not the content
i tried many times but still not output is there any alternative way to use beside awk i think sed also do it

Code:

sed "s/\(.*_\)\(....\)\(.*$\)/\1$a\3/" $file > $c

even this is not working
don't know what is not working and why output file is having no records

Code:

nawk 'FNR==1 {$1="zzz"}1' $file > $c

can you write a sample input file?

hi everyone in my previous post i wrote one command

Code:

#>awk ' { if(NR==1) { $1="zzz" } ' $file > $c

and i was saying file c is created with 0 sixe now i understand why it is creating 0 sixe
see the problem is if u r using awk and redirecting the output u must use

Code:

#>awk ' { if(NR==1) { $1="zzz";print } ' $file > $c

print statment then only it will write .

it works

thankx everyone who helped me in this

good works to you..
and you can use instead of the code

Code:

a=100
b=`echo $file  | cut -d_ -f4 | cut -d. -f1
c=`echo $file | sed "s/$b/$a/"

to

Code:

c=`echo $file | sed 's/\(.*\)_[0-9][0-9][0-9][0-9]\(_*[0-9]*\)/\1_100\2/'`

regards
ygemici