AIX

Hello all. I have a flat text file, separated into paragraphs. I need to grep for all paragraphs containing a specific term (Flash, in this case), and first line in each paragraph containing that term, along with the line immediately preceding the first occurence.

Example paragraph:

Code:

Some text, that could contain anything
Flash 1
Flash 2
Flash 3

I need to get:

Code:

Some text, that could contain anything
Flash 1

Is there a set of flags for 'grep -p', or other commands that I can use? The file has almost ten thousand paragraphs, and only 3,000 contain 'Flash'. I REALLY don't want to search by hand.

How are we supposed to identify the start of a new paragraph?

what about

Code:

grep -p -B 1 Flash | head -2

If your paragraphs are separated by blank lines then you could do something like:

Code:

awk '/Flash/ {
   for (i=1;i<=NF;i++) {
      if ($i ~ /Flash/) {
         if (i>1) {
            printf $(i-1) OFS
         }
         print $i;
         break
      }
   }
}' FS="\n" OFS="\n" RS="" ORS="\n\n" file

AIX' grep has the (non-standard, i believe) option "-p", which searches for "paragraphs" - groups of lines separated by blank lines, unless a "paragraph separator" is specified.

AIX man page of grep

bakunin

Since awk can separate on paragraphs by setting RS to "", how about this:

Code:

awk '$1 ~ R { print $1; print $2 }' FS="\n" RS="" R="mysearchstring" inputfile

My apologies for not getting back to you guys. I've had back surgery, so won't be able to try this for a few days.