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$ClientName="onbekend" ; SET $Clientname to unknown (in case of error)
$FileName = "C:\TEMP\" + @USERID + "\CLIENT.TXT" ; SET PATH to write to
RUN "%COMSPEC% /C SET CLIENTNAME > " + $FileName ; write ENVIRONMENT variables in $FileName
SLEEP 1 ; Give DOS time to wite $FileName

IF OPEN(1,$FileName)=0 ; OPEN $FileName for READ
$Regel=ucase(READLINE(1)) ;
$Gevonden="NEE" ;
WHILE @ERROR=0 AND $Gevonden="NEE" ; DO while !eof AND !found CLIENTNAME
IF INSTR($Regel,"CLIENTNAME") > 0 ; CHECK for Variable CLIENTNAME
$Gevonden="JA" ; if found SET Boolean $Gevonden True
ELSE ; CLIENTNAME !found
$Regel=READLINE(1) ; READ next line
ENDIF ; !eof AND !found
LOOP ;

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