How to use shell command in awk ?

Shell Programming and Scripting
1

Hello,
i was just wondering how can i use shell command in awk script file? say suppose i want to print the date at the top of the report i generate using awk how can i do that? Thanks in advance! :slight_smile:

2

Possibilities:

awk 'BEGIN{"date" | getline d; print d; close("date")}
{# Other commands....}
' file

Or:

awk -v d="$(date)" 'BEGIN{print d}
{# Other commands....}
' file

Or:

awk 'BEGIN{system("date")}
{# Other commands....}
' file

Regards

3

thanks Franklin52,
the last one is the easiest for me haha! and can you please tell me how can i do the following in awk script file?

 for i in `ls`
 do
      echo $i
 done
4

also why is this not working?

BEGIN{
	system("date \"+%H-%M\"")|getline d
}
{
	
}
5

Do you mean something like this?

awk 'BEGIN{
while ("ls" | getline var){
  #Do something with var...}
}
{...}'

The system command returns the exit status of the command that was executed not the output of the command.

Regards

6

Thanks again Franklin52 :slight_smile:
now things getting into my mind.