I am new with shell script. I need to save the number of files with particular extension(.properties) in a variable using shell script.
I have used
ls |grep .properties$ |wc -l
but this command prints the number of properties files in the folder. How can I assign this value in a variable.
I have tried
count=${ls |grep .properties$ |wc -l}
But it is showing error like:
./replicate.sh: line 57: ${ls |grep .properties$ |wc -l}: bad substitution
You're using the wrong brackets, it should be $() (command output substitution) rather than ${} (variable substitution).
count=$(ls -1 | grep '\.properties$' | wc -l)
You'll also notice I've use ls -1 to force one file per line in case your ls doesn't do this automatically for pipelines, and changed the pattern to match the . correctly.
You can also bypass the grep totally if you use something like:
count=$(ls -1 *.properties 2>/dev/null | wc -l)
Just watch out for "evil" filenames like those with embedded newlines for example, though my ls seems to handle these fine by replacing the newline with a ? character - that's not necessarily a good idea for doing things with files but it works okay for counting them.
There are better tools to use if you have such beasts and you need the actual file name, but they're rare enough that you generally don't have to worry about it.