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awk, extract last line of multiple files

 
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# 1  
Old 10-21-2010
awk, extract last line of multiple files
Hi,
I have a directory full of *.txt files. I would like to print the last line of every file to screen.
I know you can use FNR for printing the first line of each file, but how do I access the last line of each file?

This code doesn't work, it only prints the last line of the last file:
Code:
BEGIN {
  print "Starting script...";
}
{
  last_line = $0;
} 
END {
  printf "\n" last_line;
  printf "\nEnding script...\n";
}

Note: I prefer coding by creating a file script.awk and running it using awk -f script.awk *.txt
ThanksSmilie
# 2  
Old 10-21-2010
Code:
tail -1 file*

# 3  
Old 10-21-2010
Code:
tail: option used in invalid context -- 1

# 4  
Old 10-21-2010
Quote:
Originally Posted by Scrutinizer
Code:
tail: option used in invalid context -- 1

I get the message "tail:: Too many arguments.". Should I be replacing text in your example with text relevant to my example? I'm not familiar with a lot of the syntax.
# 5  
Old 10-21-2010
You could use tail like this:
Code:
for i in *.txt
do 
  tail -1 "$i"
done

Your script can be adjusted like this
Code:
BEGIN {
  print "Starting script...";
}
  last_file != FILENAME && NR!=FNR {
  print last_line
}
{ last_line = $0
  last_file = FILENAME
}

END {
  print last_line;
  printf "\nEnding script...\n"
}

This User Gave Thanks to Scrutinizer For This Post:
Liverpaul09
# 6  
Old 10-21-2010
Quote:
Originally Posted by Scrutinizer
You could use tail like this:
Code:
for i in *.txt
do 
  tail -1 "$i"
done

Your script can be adjusted like this
Code:
BEGIN {
  print "Starting script...";
}
  last_file != FILENAME && NR!=FNR {
  print last_line
}
{ last_line = $0
  last_file = FILENAME
}
 
END {
  print last_line;
  printf "\nEnding script...\n"
}

That works exactly like I want....fantastic! ThanksSmilie
 
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