find: paths must precede expression

Question

I am using CentOS 6.4 final in two machines. I am executing a script. The script contains the find command

path=$1
searchstring=$2 
echo `find $path -name $searchString`
for filename in `find $path -name $searchString`
do
echo "$filename"
echo
done

./findfiles.sh /var/log/ *.txt

The above script is executing fine and printing the files. But in the second machine I am getting usage error: find: paths must precede expression

The reason behind is *.txt which got expanded in find command.After changing for filename in find $path -name "$searchString" it is executing fine.

Why syntax error is not happening in first CentOS machine?

Answer 1

Quote your shell arguments:

$ ./findfiles.sh /var/log/ '*.txt'

Answer 2

You need to use proper quoting or the shell will try to expand *.txt before find sees it.

So if the current folder contains a.txt and b.txt, then find /var/log -name a.txt b.txt will be executed -> find will be confused what you want to do with b.txt

That's why it's so important to use proper quoting. Your script should be:

path="$1"
searchstring="$2" 
echo $(find "$path" -name "$searchString")
for filename in $(find "$path" -name "$searchString")
do
    echo "$filename"
    echo
done

Note that I've quotes variable assignments (otherwise, the glob expansion will happen when you define searchstring. Same when you use the variables.

No quotes around $()! If you would add quotes there, then find would return a single "word" as result.

Also always prefer $() over the old inline-eval with back-ticks. It's much more reliable, less prone to subtle errors and more readable.