ProcessGetEnv Function

Action

Gets the value for an environment variable key.

重要: This function must be called before the ProcessStart function and after the ProcessInitialize function.

注: This function can be called more than once (for every environment variable).

Include file

Kernel.bdh

Syntax

ProcessGetEnv( in  hProc      : number,
               in  sKey       : string,
               out sValue     : string,
               in  nValueSize : number ): boolean;

Return value

true if successful.
false in case of an error. The GetLastError function may be used to retrieve the system error code.

Parameter	Description
hProc	The handle that identifies the process. It is returned by the ProcessInitialize function.
sKey	Specifies the environment variable whose value is being retrieved (e.g. "temp" or "path").
sValue	This parameter retrieves the value of the specified environment variable.
nValueSize	Length of the string that receives the value for the environment variable.

Example

dcltrans
  transaction TMain
  var
    hFile      : number;
    hProcessId : number;
    nStatus    : number;
    nRead      : number;
    sData      : string;
    sPath      : string;
  begin
    // Create process and start it up...
    hProcessId := ProcessInitialize("application1.exe", PROCESS_DETACHED,
                     "", "c:\\temp\\", "c:\\temp\\out.txt");

    // set environment variable "path"
    ProcessGetEnv(hProcessId, "path", sPath, STRING_COMPLETE);
    sPath := sPath + "c:\\application1\\;";
    ProcessSetEnv(hProcessId, "path", sPath);
    RepMessage(sPath,SEVERITY_ERROR);

    // start the process
    ProcessStart(hProcessId);

    // Wait for process to finish
    Wait(25.0);

    // Kill the process if it hasn't finished yet
    nStatus := ProcessGetState(hProcessId);
    if (nStatus <> PROCESS_STATE_FINISHED) then
      ProcessKill(hProcessId, PROCESS_KILLSINGLE);
    end;

    // Read the output of the process, written to a file
    FOpen(hFile, "c:\\temp\\out.txt", OPT_FILE_ACCESS_READ, OPT_FILE_OPEN);
    while FRead(hFile, sData, 1, nRead) do
      Write(sData);
    end;

    FClose(hFile);
    ProcessFree(hProcessID);
  end TMain;