Contributor: GARY MAYS
{>> How do I detect / read a string in the enviornment? For example> WriteLn('The DOS variable "COMSPEC" = ",GetEnv('COMSPEC'));
If you are using an older version of pascal without the getenv function, then
here are two functions to get the environment string and executed program name
that I wrote a while ago. It can examime any environment, not just the current
program... you just provide the prefix segment...
}
{--get the text of an environment string variable--}
function getenvstr(_prefixseg: word; v : string): string;
{ gary a. mays 3/1/88 }
type
envstr = array[1..32768] of char;
var
env : ^envstr;
p : integer;
temp : string;
i : integer;
begin
if v = '' then
begin
getenvstr := '';
exit;
end;
{ convert specified variable name to uppercase }
for i := 1 to length(v) do v[i] := upcase(v[i]);
env := ptr(memw[_prefixseg:2ドルc],0);
i := 1;
temp := '';
while env^[i] #0 do
begin
temp := temp + env^[i];
i := succ(i);
if env^[i] = #0 then { end of current string }
begin
i := succ(i);
p := pos('=',temp) + 1;
if p> 1 then
if v = copy(temp,1,p-2) then { caller's variable name matched }
begin
getenvstr := copy(temp,p,255); { return variable's value }
exit;
end;
temp := '';
end;
end;
getenvstr := '';
end; { getenvstr }
{--get the executed program name--}
function getprogramname(_prefixseg: word): string;
{ gary a. mays 5/11/88 }
type
envstr = array[1..32768] of char;
var
env : ^envstr;
p : integer;
temp : string;
i : integer;
begin
env := ptr(memw[_prefixseg:2ドルc],0);
i := 1;
temp := '';
while env^[i] #0 do
begin
repeat i := succ(i); until env^[i] = #0; {locate end of a string}
i := succ(i); { point to next string or final nul }
end;
i := i + 3; { point to start of asciz string }
while env^[i] #0 do
begin
temp := temp + env^[i];
i := succ(i);
end;
getprogramname := temp;
end; { getprogramname }