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Date: Mon, 25 May 2026 06:38:16 +1000
Message-ID: <CAKVXxD_XNsFe-96L61FppVzB2SRECWG971FrGwMQ43_FFzOcPg@mail.gmail.com>
Subject: [PHP-DEV] Documenting sscanf()'s and fscanf's underflow
To: internals <internals@lists.php.net>
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From: mickmackusa@gmail.com (mickmackusa)

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Hi all, may I request that the documentation pages for sscanf() and
fscanf() be reviewed?

Last week, I tripped over a bug in my code because, despite using and
loving sscanf() for many years, the function unexpectedly returned -1 for
the number of successful captures when I expected 0.

I've documented the encounter here:
https://stackoverflow.com/q/79942833/2943403

I have been doing a fair amount of Google searching, but either my keywords
are not ideal or there really is no mention of this floating around (even
the C++ pages that I read don't mention it).

Thanks,
mickmackusa

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<div dir=3D"auto">Hi all, may I request that the documentation pages for ss=
canf() and fscanf() be reviewed?<div dir=3D"auto"><br></div><div dir=3D"aut=
o">Last week, I tripped over a bug in my code because, despite using and lo=
ving sscanf() for many years, the function unexpectedly returned -1 for the=
 number of successful captures when I expected 0.</div><div dir=3D"auto"><b=
r></div><div dir=3D"auto">I&#39;ve documented the encounter here:=C2=A0<a h=
ref=3D"https://stackoverflow.com/q/79942833/2943403">https://stackoverflow.=
com/q/79942833/2943403</a></div><div dir=3D"auto"><br></div><div dir=3D"aut=
o">I have been doing a fair amount of Google searching, but either my keywo=
rds are not ideal or there really is no mention of this floating around (ev=
en the C++ pages that I read don&#39;t mention it).</div><div dir=3D"auto">=
<br></div><div dir=3D"auto">Thanks,</div><div dir=3D"auto">mickmackusa</div=
></div>

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