Process Utilities

ACT process utilities enable you to execute any outside program with a single method call. To do this, you call the method Start exposed on the object ExtAPI.ProcessUtils.

The following APIs are available:

Class	Member	Description
`ExtAPI.ProcessUtils`	`Start(target, args)`	Starts an application, file, or other target. Returns an integer error code from the resulting process. Waits for process to exit.
`ExtAPI.ProcessUtils`	`Start(target, useShell, args)`	Starts an application, file, or other target. `useShell` indicates whether or not to use the running OS’s shell to execute the target.

A sample implementation of process utilities follows.

import System

def update(task):
    activeDir = task.ActiveDirectory
    extensionDir = task.Extension.InstallDir
    exeName = "ExampleAddinExternalSolver.exe"
    solverPath = System.IO.Path.Combine(extensionDir, exeName)
    
    inputValue = task.Properties["Inputs"].Properties["Input"].Value
    
    inputFileName = "input.txt"
    outputFileName = "output.txt"
    dpInputFile = System.IO.Path.Combine(activeDir, inputFileName)
    dpOutputFile = System.IO.Path.Combine(activeDir, outputFileName)
    
    #write input file
    f = open(dpInputFile, "w")
    f.write('input='+inputValue.ToString(System.Globalization.NumberFormatInfo.InvariantInfo))
    f.close()
    
    exitCode = ExtAPI.ProcessUtils.RunApplication(solverPath, dpInputFile, dpOutputFile)
    if exitCode != 0:
        raise Exception ('External solver failed!')
    #read output file
    
    outputValue = None
    f = open(dpOutputFile, "r")
    currLine = f.readline()
    while currLine != "":
        valuePair = currLine.split('=')
        outputValue = System.Double.Parse(valuePair[1], System.Globalization.NumberFormatInfo.InvariantInfo)
        currLine = f.readline()
    f.close()
    
    if outputValue == None:
        raise Exception("Error in update - no output value detected!")
    else:
        task.Properties["Outputs"].Properties["Output"].Value = outputValue