an example can be found on AMOSPro_Tutorial:Tutorials/Procedures_2.AMOS
Called inside a procedure to allow you to access a variable from your main program.
Shared variable list.
You can also define your shared variables using STRINGS containing wildcards such as "*" or "?".
"*" means "Use any group of characters up to the next letter or number"
"?" means "Use any single character in the current position"
Only string CONSTANTS can used for this purpose.