Applying Unix's Head on AWK Through Find Command

Question

I want to output top 10 lines of AWK command in the list of files given by find, using this snippet:

$ find . -name "*.txt" -print -exec awk '$9 != ""'  \| head -n10 {} \;

Note also that I want to print out the file names being processed.

But why I get such error:

awk: cmd. line:2: fatal: cannot open file `|' for reading (No such file or directory)
./myfile.txt

What's the right way to do it?

I tried without backslash before the pipe. Still it gave an error:

find: missing argument to `-exec'
head: cannot open `{}' for reading: No such file or directory
head: cannot open `;' for reading: No such file or directory

Answer 1

You can do it this way too:

find . -name '*txt' -print -exec awk 'BEGIN {nl=1 ;print FILENAME} $9 !="" {if (nl<11) { print $0 ; nl = nl + 1 }}' {}  \;

without head.

Answer 2

When running a command with find's -exec, you don't get all the nice shell things like the pipe operator (|). You can regain them by explicitly running a subshell if you like though, eg:

find . -name '*.txt' -exec /bin/sh -c "echo a text file called {} | head -n 15" \;

Answer 3

Using awk only should work:

find . -name "*.txt" -print -exec awk '{if($9!=""&&n<11){print;n++}}' {} \;

Answer 4

If you want to run an Awk program on every file from find that only prints the first 10 lines each time.

$ find . -name "*.txt" -print -exec awk '$9 != "" && n < 10 {print; n++}' {} \;

Answer 5

Based on Ashawley's answer:

find . -name "*.txt" -print -exec awk '$9 != "" {print; if(NR > 9) exit; }' {} \;

It should perform better, as we exit awk after the 10th record.

Answer 6

I'm getting the following error. does any one knoe how to fix it

$ sh skipper.sh file1 filea fileb filec filec fileb filea fileb filec fileb awk: cmd. line:2: (FILENAME=filec FNR=7) fatal: cannot open file `file10' for re ading (No such file or directory)

here is my code

awk -v nfiles="10" 'NR==FNR{a[$0]++;next}
$0 in a {a[$0]++; next}
{b[$0]++}
END{
  for(i in a){
    if(a[i]==nfiles) {
      print i > "output1"
    }
    else if(a[i]==1) {
        print i > "output3"
    }
  }
  for(i in b){
    if(b[i]==nfiles-1) {
        print i > "output2"
    }
  }
}' $1 $2 $3 $4 $5 $6 $7 $8 $9 $10