SWPRUNCMD() / SWPRUNCMDBAS()  Execute child process.
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 Function : Execute a child process.

 Syntax   : lValue = SWPRUNCMD(cCommand, nuMem, cRunPath, cTempPath)

 Return   : TRUE if the command interpreter was executed.
            FALSE if an error occurred

 This function executes a child process of the current program, freeing
 conventional memory occupied by the parent program. Any non conventional
 memory used by the parent will remain allocated.

 The parameters to SWPRUNCMD() are as follows:

 cCommand: The name of the program, batch file or DOS internal command to be
 executed, followed by any required parameters. An empty string will cause
 the command interpreter to be loaded, giving a DOS prompt.

 nuMem: The amount of memory in kilobytes (kb) to be freed prior to executing
 the child process. If this parameter is passed as zero, as much memory as
 possible will be freed.

 cRunPath: The drive and directory to make current prior to executing the
 child process.

 cTempPath: The drive and directory where the swap function should create a
 disk swap file containing the image (or partial image) of the parent
 program. Note that XMS and EMS memory will be used in preference to a disk
 swap file if available provided their use has not been prohibited through
 the use of SWPUSEEMS() and SWPUSEXMS().

 Note  that this parameter may be overridden at runtime through the use of
 the SWAP or BLINKER environment variables. For example:

    SET SWAP=F:\TEMP;

 or

    SET BLINKER=/SDF:\TEMP

 will cause the temporary diskfile to be created in F:\TEMP, regardless of
 the value passed as a parameter to the SWPRUNCMD().

 The swap function will always invoke the current command interpreter as
 specified in the COMSPEC environment variable, which in turn will execute
 cCommand. This allows the parent program to execute any internal or external
 DOS command, a batch file or any program which can be executed from the DOS
 prompt. The return code of the child process can be retrieved using the
 function SWPERRLEV().

 The return value is a logical (boolean) value indicating the success of the
 SWPRUNCMD() call. Following an unsuccessful call to SWPRUNCMD(), the program
 can use SWPERRMAJ() and SWPERRMIN() to determine the nature of the error.

 Example:

    success = SWPRUNCMD("",0,"","")

 Shell to DOS, freeing as much memory as possible, save swap file to current
 directory if required.

    success = SWPRUNCMD("WIN",0,"C:\WINDOWS","F:\")

 This command will execute Microsoft Windows, freeing as much memory as
 possible. The swap function will change drive and directory to C:\WINDOWS
 prior to executing the WIN command. If a temporary disk swap file is
 required, it will be created on F:\

    success = SWPRUNCMD("DIR /W",100,"","")
    IF (!success)
       ? "Swap failed"
       majerr = SWPERRMAJ()
       minerr = SWPERRMIN()
       ? "Error codes :", majerr, minerr
    ELSE
       ? "Swap succeeded"
       ? "Errorlevel :", SWPERRLEV()
    ENDIF

 Execute the DOS DIR command, first freeing 100KB, cretae the swap disk file
 to the current directory if required. On return, check the swap function
 return code. If the swap failed display the swap major and minor error
 codes, if it succeeded, display the return code of the child process.

    success = SWPRUNCMD("RRUN ABC",0,"","")
    IF (!success)
       ? "Swap failed"
          majerr = SWPERRMAJ()
          minerr = SWPERRMIN()
          ? "Error code :", majerr, minerr
       ELSE
       ? "Swap succeeded"
       ? "Errorlevel :",SWPERRLEV()
    ENDIF

 Execute the R & R report writer, checking for errors on return.