RE: [Dev-C++] itoa - atoi : another implementation

[Ioannis V. <iv...@em...>]

> -----Original Message-----
> From: Per Westermark [mailto:pw...@ia...]=20
> Sent: Wednesday, April 02, 2003 10:13 PM
> To: Ioannis Vranos
> Cc: 'Dev-C++'
> Subject: RE: [Dev-C++] itoa - atoi : another implementation=20
>=20
>=20
> You might have been in even more hurry :-)
>=20
> How many characters do you allocate if the integer was zero,=20
> or negative?



Yes you are right, I forgot the <=3D0 stuff. Well I leave it as an =
exercise
for home. :)



>=20
> And then of course - itoa() with a sprintf() is of very=20
> little use, since
> it doesn't solve reentrancy problems,


What do you mean.



> doesn't support variable number
> base,


No it doesn't.


> and doesn't allow linking without the formatted RTL code.


What do you mean.


=20
> It isn't even a good optimization of number of source code
> characters, since each call MUST be either:
>     free(itoa(i1));
> which is an expensive NOP instruction, or:


It is supposed to be used where free store usage is affordable (almost
everywhere these days). No specific constraint requirements were =
provided by
the OP.



>     char *p =3D itoa(i1);
>     use_string(p);
>     free(p);
> which isn't much shorter than
>     char buf[20];
>     sprintf(buf,"%d",i1);
>     use_string(buf);



Yes it isn't. That's why I said itoa() is not needed.



=20
> Whith a static buffer in itoa() you get code length improvement
> with:
>     use_string(itoa(i1));


The above is not thread safe (since as I saw you try to embarrass me). =
:)
You must place a locking mechanism.


> and with a semi-standard implementation of itoa you get code length
> improvement AND extra number bases:
>     char buf[30];
>     use_string(itoa(i1,buf,3)); // trinary output


I do not know any standard or semi-standard impleentation of itoa(). =
Even in
K&R2 it is not what you are talking about.




Ioannis Vranos
=20
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