Re: fcvt safety

From:
"Igor Tandetnik" <itandetnik@mvps.org>
Newsgroups:
microsoft.public.vc.language
Date:
Mon, 18 Dec 2006 08:47:17 -0500
Message-ID:
<OJXL9rqIHHA.4000@TK2MSFTNGP06.phx.gbl>
"SteveB" <steve@thebretts.co.uk> wrote in message
news:1166446711.893067.160070@t46g2000cwa.googlegroups.com

When I read the info about fcvt using a statically allocated buffer
for subsequent calls I assumed that this meant calls to this function
within the same object. The object in question is a single threaded
com object. The function itself would be called by more than one
class (2) and i'm working on the assumption that these two objects
won't be created at the same time (the code creates them
sequentially, could the execution create them as it sees fit ?).

Will my app be safe ?


You are fine as long as you don't do something like this:

char* p = _fcvt(x, ...);
DoSomething(); // may itself use _fcvt
printf(p); // do something with p

In other words, use or copy data out of that static buffer right after
the call.

Alternatively, use sprintf or similar to format into the buffer you
provide, or ostringstream to format into a dynamic buffer maintained by
the class.
--
With best wishes,
    Igor Tandetnik

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