add line to files containing phrase

[blackbox111]

I am writing a script that finds all files (in the pwd) that have the .c extension and it searches them for print and pfrintf. If either are found, the line #include <stdio.h> is added, unless it's already there.

I am using egrep -c 'f?printf' *.c | cut -d: -f 2 to determine whether there are any occurrences, and then I'll do echo "#include <stdio.h>\n$(cat file)" > temp" and "mv temp file". The trouble is that I don't know what file should be.

I was planinng on using a shell script but should I be using sed instead?

[secondmouse]

I am writing a script that finds all files (in the pwd) that have the .c extension and it searches them for print and pfrintf. If either are found, the line #include <stdio.h> is added, unless it's already there.

I am using egrep -c 'f?printf' *.c | cut -d: -f 2 to determine whether there are any occurrences, and then I'll do echo "#include <stdio.h>\n$(cat file)" > temp" and "mv temp file". The trouble is that I don't know what file should be.

I was planinng on using a shell script but should I be using sed instead?

You are right about using sed, but you don't need to use temp file. sed supports inline editing (option -i).

find . -iname "*.c"|while read file; do [ `egrep f?printf $file` ] && sed -i '1i\
#include <stdio.h>' $file; done

Yet a simpler version would be

egrep -l f?printf *.c | while read file; do sed -i '1i\
#include <stdio.h>' $file; done

if you only care about all .c files under current directory excluding all sub-directories.