sscanf for delphi

Nigel Parsons

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Dec 11, 1996, 3:00:00 AM12/11/96

to

I found the following on usenet archives courtesy of hu...@pobox.com. I
can't
get it working properly. I've emailed the author but have not received
a
reply.

This is the problem I'm having:
Being new to pascal I can't quite work out how to pass the parameters
to
the function ie in 'C':

char abc[6];
int i;

sscanf("word 6","%s %d",abc,&i);

this makes abc = "word" and i = 6

equates to pascal

abc : string;
i : integer;

sscanf('word 6','%s %d',???????);

what goes at the ???????

If you know the answer or have found another solution for sscanf or
strtok,
please let me know.

Code follows:

function sscanf(Input, Format : PChar; var ArgList) : PChar;
type
WordPtr = ^word;
LongPtr = ^longint;
PCharPtr = ^PChar;
var
DelimPos : PChar;
ArgPtr : PChar;
n : longint;
FmtCmd : char;
code : integer;
LongCmd : boolean;
LenStr : string[8];
MaxLen : integer;
begin
sscanf := nil;
ArgPtr := addr(ArgList);
if (Format = nil) then Exit;
while (Format^ <> #0) do begin
if (Input = nil) or (Input^ = #0) then Exit; { ***ERROR }
if Format^ = '%' then begin
inc(Format);
FmtCmd := Format^;

if FmtCmd in ['0'..'9'] then begin
LenStr := '';
repeat
LenStr := LenStr + FmtCmd;
inc(Format);
FmtCmd := Format^;
until not (FmtCmd in ['0'..'9']);
if LenStr <> '' then begin
Val(LenStr, MaxLen, code);
if code <> 0 then Exit;
end;
end else
MaxLen := $7FFF;

if FmtCmd = 'l' then begin
LongCmd := true;
inc(Format);
FmtCmd := Format^;
end else
LongCmd := false;

case FmtCmd of
'c' : begin
ArgPtr^ := Input^;
inc(ArgPtr, 2);
end;
'd','i','u','s','*' : begin
{ look for delimiter }
DelimPos := StrScan(Input, (Format+1)^);
if DelimPos <> nil then begin
if (DelimPos-Input > MaxLen) then Exit;
DelimPos^ := #0; { zero delimiter }
end;

if FmtCmd = 's' then begin
if PCharPtr(ArgPtr)^ = nil then { if dest. string is NIL }
PCharPtr(ArgPtr)^ := StrNew(Input) { then allocate a new
one }
else
StrCopy(PCharPtr(ArgPtr)^, Input); { else copy to dest
buffer }
end else
if FmtCmd <> '*' then
Val(Input, n, code);

if DelimPos <> nil then DelimPos^ := (Format+1)^; { set it
back }
case FmtCmd of
's' : inc(ArgPtr, 4);
'*' : ; { dummy }
else
if code <> 0 then Exit; { could not convert }
if LongCmd then begin
LongPtr(ArgPtr)^ := n;
inc(ArgPtr, 4);
end else begin
WordPtr(ArgPtr)^ := LongRec(n).Lo;
inc(ArgPtr, 2);
end;
end;
Input := DelimPos; { move input pointer to delimiter }
end;
else
Exit;
end;
inc(Format);
end else begin
if Input^ <> Format^ then Exit;
inc(Format);
inc(Input);
end;
end;
sscanf := Input;
end;

Regards

-----------------------------------------------------------------
Nigel....@agiltd.co.uk
----------------------------------------------------------------

Chami

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Dec 12, 1996, 3:00:00 AM12/12/96

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sscanf( 'word 6', '%s %d', [ abc, i ] );

--
http://www.ChamisPlace.com/delphi/
The place to get new Delphi tips and tricks daily

Nigel Parsons <ni...@agiltd.demon.co.uk> wrote in article
<85031840...@agiltd.demon.co.uk>...

Nigel Parsons

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Dec 13, 1996, 3:00:00 AM12/13/96

to

Thanks for suggestion. I tried it and got:

Error: Constant Object cannot be passed as var reference

Richard MacDonald

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Dec 13, 1996, 3:00:00 AM12/13/96

to

On Fri, 13 Dec 1996 08:20:30 GMT, ni...@agiltd.demon.co.uk (Nigel Parsons)
may have written:

Try putting the 'word 6' into a variable. Then it will work.
Dick MacDonald

Nigel Parsons

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Jan 7, 1997, 3:00:00 AM1/7/97

to

"Chami" <7222...@compuserve.com> wrote:

>sscanf( 'word 6', '%s %d', [ abc, i ] );

This doesn't work as the sscanf function appears to be expecting
an untyped list or array of pointers. The format string is then used
to determine the type of the variable to which the pointer is
pointing. Passing the variables in the manner you suggest doesn't
generate a list of pointers.

Thanks anyway.

Nigel....@agiltd.co.uk