Renaming multiple files based on their contents

Question

How can I rename all files within a folder with the first word of their content? For example if a.txt contains “Unix is an OS” in its first line then a.txt should be renamed to Unix.txt

Answer 1

Try this:

for f in *.txt; do d="$(head -1 "$f" | awk '{print $1}').txt"; if [ ! -f "$d" ]; then mv "$f" "$d"; else echo "File '$d' already exists! Skiped '$f'"; fi; done

or more long variant (as script):

#!/bin/sh
for f in *.txt; do
    d="$(head -1 "$f" | awk '{print $1}').txt"
    if [ ! -f "$d" ]; then
        mv "$f" "$d"
    else
        echo "File '$d' already exists! Skiped '$f'"
    fi
done

In case when destination file exists this one-liner skips it.

Answer 2

Here is my approach.

#!/bin/bash
for file in *; 
do
    if [[ -f $file ]]; 
    then
        # cut word by single white space
        fileword=$(head -n1 "$file" | cut -f1 -d" ");
        # Everything after first dot is considered as extention
        ext=$(echo $file | sed 's/.*\.\(.*\)/.\1/g')
        [ "$file" != "$fileword" ] && $(mv  "$file"  "$fileword$ext")
    fi;
done

Answer 3

Use this oneliner

for i in *; do if [ ! -f $i ]; then echo "skipping $i"; else newname=`head -1 $i | sed 's/^\s*\([a-zA-Z0-9]\+\).*$/\1/'`; [ -n "$newname" ] && mv -i $i $newname.txt || echo "error at: $i"; fi; done

This will replace all files with the first word in that file + .txt. I defined first word to be the first occurrence of [a-zA-Z0-9]+, discarding leading white spaces.
Disclaimer: Please just use it if you are sure that there is a first word on line one in each file! Otherwise you might experience unexpected results ;-)

Answer 4

for i in *.txt
do
d="$(head -1 "$i" | cut -d " " -f1).txt";
mv "$i" "$d"
done

Answer 5

for i in *.txt; do mv "$i" "$(head -1 "$i")".txt; done

Answer 6

On your own risk: :)

find -exec echo -n mv {} " " ";" -exec sed '1s/ .*//;q' {} ";" > tmp.sh && bash tmp.sh

This works with easy filenames, containing easy words. A file "O'Reilly" containing as first word "Eto'o" will fail. Miserably.