Use "system" instruction.

Check online help:
online-help.sageerpx3.com/.../4gl_system.html

"System allows you to execute system commands and to obtain the information sent by the command on the standard output.
...."

Here is an example from there:

# Copy FILE1 to FILE2 with stderr redirection on UNIX
System "cp "+FILE1+" "+FILE2-"2>/dev/null"

# List of a directory on a Windows server on which the first reference folder is located
# Returns the list of files and the number of lines read
# If no directory is given we default it with a temporary directory
Subprog DIRECTORY_LIST(FILES,DIRECTORY,NUMBER)
Variable Char FILES(100)(1..)
Value Char DIRECTORY(100)
If DIRECTORY="" : DIRECTORY = "C:\sage\tmp" : Endif
System FILES = adxmac(1)+"@DIR/b/o:n"+DIRECTORY
NUMBER=stat1
End

I'm trying to use System to run a .bat file saved on x3 server but I fail. What can I do?
I can't even run the same instruction of the online help.