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kenw232 09-14-2016 03:08 PM
Find length of fist line of all txt files
 
I want to loop through all the .TXT files in a directory and get the length of the first line of each one.

find /path -name "*.txt" -exec head -n1 {} \;
will print the first line of each file, now how do I print the LENGTH of the first line of each file? like "300" for 300 characters long.

Sefyir 09-14-2016 03:20 PM
Use wc

Code:
echo hello | wc -c
6
Code:
      -c, --bytes
              print the byte counts

kenw232 09-14-2016 03:24 PM
ya buts its counting all the output together

Code:
find . -name "*.php" -exec head -n1 {} \; | wc -c
1364901

Sefyir 09-14-2016 03:30 PM
You can use a while loop to pipe each line found with find

Code:
while read i;
do head -n1 "$i" | wc -c
done < <(find . -name \*.php)
You can also use parallel

Code:
parallel 'head -n1 {} | wc -c' ::: \*.php

kenw232 09-14-2016 03:35 PM
This is good. Now I just need a condition if the length from wc is equal to say 400 to do something. How do I tell this to do a sed command if the length of the first line is 400 characters?

PHP Code:
while read i;
do head -n1 "$i" | wc -c
done < <(find . -name \*.php) 

Sefyir 09-14-2016 03:42 PM
This can easily be done with a if conditional expression.

Feel free to use man bash and search for CONDITIONAL EXPRESSIONS

Here's a search to get you started

eg this guide

kenw232 09-14-2016 03:50 PM
yes I can do a conditional expression. but how to I capture the number of wc into a variable to check?

Sefyir 09-14-2016 03:59 PM
You can use command substitution for that.

Code:
variable=$(echo hello | wc -c)

echo $variable
6

Habitual 09-14-2016 04:04 PM
Couting characters, words, lenght of the words and total lenght in a sentence

and
https://www.google.com/#q=count+word...in+bash+script

Read.
Study.
Try.
Question.

MadeInGermany 09-18-2016 10:40 AM
Code:
find /path -name "*.txt" |
while IFS= read -r file
do
  read line <"$file"
  if [[ ${#line} -eq 400 ]]
  then
    echo "${file}: line1 is 400"
  fi
done


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