Locate specific file from script

I've written a script file in which, one function searches for another script and if found, executes that script.

Script extract

#!/bin/bash
...
service_status() {
local my_script=`which my-services-check.sh 2>/dev/null`
[[ -z "$my_script" ]] && { echo -n "functionality not available" ; failure ; echo ; return ; }
source $my_script    
}
...

When I do which my-services-check.sh 2>/dev/null from the terminal, it returns the correct path to that file.

When I run that function service_status() (when calling the script), it doesn't find the file ($my_script is empty).

Instead of using which I've tried with type and command but I end up with the same result.

Path issue

Then I printed out $PATH from the terminal and from the script, and sure enough they aren't the same! When executed from my script, the $PATH is set to be the secure PATH, as defined in /etc/sudoers:

Defaults secure_path = /sbin:/bin:/usr/sbin:/usr/bin

From the terminal

echo $PATH /usr/lib64/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin: ...

So,

1. 
   

   how can I reliably find the file I'm looking for, from my script? (without using find as the file I need must be in the PATH)?

   
   


2. 
   

   and how come the PATH is set differently when executed from a script?