standard.execute

Executes a command on the front-end platform, with or without waiting.

Syntax

ui.Interface.frontCall("standard", "execute",
 [cmd,wait], [result]) 
  1. command - The command to be executed.
  2. wait - The wait option (TRUE=wait, FALSE=do not wait).
  3. result - The execution status (TRUE=success, FALSE=error).

Usage

The "execute" front call runs a command on the front-end platform, with or without waiting option.

This front call is only supported with the desktop front-end (GDC). When using a browser and the GAS, due to browser security limitation, it is not possible to start a process on the end user workstation.

If the second parameter is set to TRUE, the runtime system will wait until the front-end gives the control back after the local command was executed.

With the front-end running on Microsoft™ Windows™ systems platforms, depending on the program to be executed, you may need to add the "cmd /C" command before the executable name and program arguments.

With the front-end running on a Unix-like platform, shell scripts need to be preceeded with the shell program (sh or bash).

OS commands return an exit status where zero means a success, while a non-zero exit status indicates a failure, that typically reflects the system error it encountered. When the command produces a zero exit status, the standard.execute front call will return TRUE/1. When the command returns a non-zero exit status, the front call will return FALSE/0. This is only valid when the front call waits for the end of the command execution.

When specifying a file path, pay attention to platform specific rules regarding directory separators and space characters in filenames. When the front-end executes on a recent Microsoft Windows system, you can use the / slash character as directory separator, like on Unix systems. A directory or filename can contain spaces, and there is no need to surround the path with double quotes in such case. When using backslash directory separators, make sure to escape backslash characters in string literals with \\.

Example

For Microsoft Windows system:

-- Using backslash as directory separator:
CALL ui.Interface.frontCall("standard", "execute",
     ["C:\\Program Files\\FourJS\\gdc\\bin\\gdc.exe --help",FALSE], [res] )

-- Using slash as directory separator:
CALL ui.Interface.frontCall("standard", "execute",
     ["C:/Program Files/FourJS/gdc/bin/gdc.exe --help",FALSE], [res] )