Remove whitespace from a string in bash

If the file /etc/foo.props contained:

context-root= /app1 
http_port= 8080 
admin-port= 9090

... and you were using

http_port=$(cat /foo/props.conf | grep http-port | cut -d = -f 2

$http_port would end up being prefixed by whitespace, which would be a problem if you were using this to construct a URL in a script. To resolve this, you could use xargs as follows:

http_port=$(cat /etc/foo.props | grep http-port | cut -d = -f 2 | xargs)