In gedit, go to "Edit", "Preferences". Then select "plugins" and check
"External tools".

Then go to "Tools", "External tools..." and add a new tool:

name it: "FiveLinux"
description: "FiveLinux"
shortcut key: (press) F5
Command(s):

!/bin/sh

name=$GEDIT_CURRENT_DOCUMENT_NAME;
file=${name%.*};
./build.sh $file;

input: current document
output: display in bottom pane

That's all