Groups > comp.lang.c > #17583 > unrolled thread

Has Implicit Int been disabled in the new C11 standard? What about other previously depreciated constructions eg gets?

Started by	Lord Voldermort <nospam@nospam.com>
First post	2012-02-18 22:18 +0000
Last post	2012-03-01 05:57 -0500
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#17583 — Has Implicit Int been disabled in the new C11 standard? What about other previously depreciated constructions eg gets?

From	Lord Voldermort <nospam@nospam.com>
Date	2012-02-18 22:18 +0000
Subject	Has Implicit Int been disabled in the new C11 standard? What about other previously depreciated constructions eg gets?
Message-ID	<jhp83t$3un$1@speranza.aioe.org>

As per subject.

Thanks.

Tom R.

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#17584

From	Lord Voldermort <nospam@nospam.com>
Date	2012-02-18 22:36 +0000
Message-ID	<jhp94s$7c4$1@speranza.aioe.org>
In reply to	#17583

Lord Voldermort writes:
> As per subject.
> 
> Thanks.
> 
> Tom R.

*BUMP*

Anyone able to answer this q?

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#17585

From	Ben Bacarisse <ben.usenet@bsb.me.uk>
Date	2012-02-18 22:55 +0000
Message-ID	<0.598e876e0929d611c5da.20120218225555GMT.87fwe7hhtw.fsf@bsb.me.uk>
In reply to	#17584

Lord Voldermort <nospam@nospam.com> writes:

> Lord Voldermort writes:
>> As per subject.
>> 
>> Thanks.
>> 
>> Tom R.
>
> *BUMP*
>
> Anyone able to answer this q?

I'd have a go if I knew what you meant by "disabled".  By the way, 18
minutes is not a long time on Usenet, and "bumping" a thread usually
just annoys people.

-- 
Ben.

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#17599

From	Kaz Kylheku <kaz@kylheku.com>
Date	2012-02-19 06:05 +0000
Message-ID	<20120218220512.227@kylheku.com>
In reply to	#17584

On 2012-02-18, Lord Voldermort <nospam@nospam.com> wrote:
> Lord Voldermort writes:
>> As per subject.
>> 
>> Thanks.
>> 
>> Tom R.
>
> *BUMP*

Don't do this; Usenet is not a web bulletin board.

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#17586

From	Keith Thompson <kst-u@mib.org>
Date	2012-02-18 15:01 -0800
Message-ID	<lnobsveofu.fsf@nuthaus.mib.org>
In reply to	#17583

Lord Voldermort <nospam@nospam.com> writes:
> As per subject.
>
> Thanks.
>
> Tom R.

This is Usenet, not a web form or chat room.  I suggest reading
some of the other articles posted here to get a feeling for the
best style.

Please put your question in the body of the post, not just in
the title.

Posting again after 18 minutes to "bump" the original post is not
useful.  If you don't get a response after a day or so, it *might*
be time to worry.

Your actual questions, copied from the title:

> Has Implicit Int been disabled in the new C11 standard?

Implicit int was removed from the language by the C99 standard.
(C11 did not restore it.)  Many, probably most, C compilers still
support it as an extension (or just because they don't yet conform
to C99).

> What about other previously depreciated constructions eg gets?

The gets function was removed completely.

I'm not aware of any other deprecated (note spelling) features that were
removed by C11.  In particular, old-style function declarations and
definitions are still in the language.

You can get a draft, nearly equivalent to the final C11 standard, at
<http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf>.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#17602

From	Lord Voldermort <nospam@nospam.com>
Date	2012-02-19 10:54 +0000
Message-ID	<jhqkco$g1$1@speranza.aioe.org>
In reply to	#17586

Keith Thompson writes:
> Lord Voldermort <nospam@nospam.com> writes:
>> As per subject.
>>
>> Thanks.
>>
>> Tom R.
> 
> This is Usenet, not a web form or chat room.  I suggest reading some of
> the other articles posted here to get a feeling for the best style.
> 
> Please put your question in the body of the post, not just in the title.
> 
> Posting again after 18 minutes to "bump" the original post is not
> useful.  If you don't get a response after a day or so, it *might* be
> time to worry.
> 
> Your actual questions, copied from the title:
> 
>> Has Implicit Int been disabled in the new C11 standard?
> 
> Implicit int was removed from the language by the C99 standard. (C11 did
> not restore it.)  Many, probably most, C compilers still support it as
> an extension (or just because they don't yet conform to C99).
> 
>> What about other previously depreciated constructions eg gets?
> 
> The gets function was removed completely.
> 
> I'm not aware of any other deprecated (note spelling) features that were
> removed by C11.  In particular, old-style function declarations and
> definitions are still in the language.
> 
> You can get a draft, nearly equivalent to the final C11 standard, at
> <http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1570.pdf>.

Thx for the info Keiht, sorry about breech of protocol - didnt see a way 
to tell how many ppl are in this room so didnt know whether it was empty 
or ppl just missed my post.

So is there any translation program then to take code for the previous 
standard and upgrade it to work with C11 (replace gets by fgets etc)?

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#17603

From	Ben Bacarisse <ben.usenet@bsb.me.uk>
Date	2012-02-19 12:21 +0000
Message-ID	<0.2067cba4440d7d3b9d58.20120219122155GMT.87ty2nf1y4.fsf@bsb.me.uk>
In reply to	#17602

Lord Voldermort <nospam@nospam.com> writes:
<snip>

> Thx for the info Keiht, sorry about breech of protocol - didnt see a way 
> to tell how many ppl are in this room so didnt know whether it was empty 
> or ppl just missed my post.

Have a read of this: http://en.wikipedia.org/wiki/Usenet to get an
overview.

> So is there any translation program then to take code for the previous 
> standard and upgrade it to work with C11 (replace gets by fgets etc)?

In a way, yes.  Your compiler can help if you if you ask for conformance
to a specific standard.  That is likely to flag up problems, but it
won't fix them, of course.  Some, like calls to gets, can't be fixed
automatically because the problem is that the function just does not
have enough information to do a safe job.  Each call needs to be looked
at by someone who understands the code.

If the code is very old (pre-C90, often called K&R C) you'd have to have
a good reason to update it because the move to prototypes alters the way
a function is called in subtle ways.  If in doubt, ask about that
specifically.

-- 
Ben.

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#17617

From	Lord Voldermort <nospam@nospam.com>
Date	2012-02-19 19:53 +0000
Message-ID	<jhrk06$h7r$1@speranza.aioe.org>
In reply to	#17603

Ben Bacarisse writes:
> Lord Voldermort <nospam@nospam.com> writes: <snip>
> 
>> Thx for the info Keiht, sorry about breech of protocol - didnt see a
>> way to tell how many ppl are in this room so didnt know whether it was
>> empty or ppl just missed my post.
> 
> Have a read of this: http://en.wikipedia.org/wiki/Usenet to get an
> overview.

Didnt have time to read all that, but just flicking through I didnt see 
anything about listing other people currently in this room/browsing the 
forum/whatever you want to call it.

>> So is there any translation program then to take code for the previous
>> standard and upgrade it to work with C11 (replace gets by fgets etc)?
> 
> In a way, yes.  Your compiler can help if you if you ask for conformance
> to a specific standard.  That is likely to flag up problems, but it
> won't fix them, of course.  Some, like calls to gets, can't be fixed
> automatically because the problem is that the function just does not
> have enough information to do a safe job.  Each call needs to be looked
> at by someone who understands the code.
> 
> If the code is very old (pre-C90, often called K&R C) you'd have to have
> a good reason to update it because the move to prototypes alters the way
> a function is called in subtle ways.  If in doubt, ask about that
> specifically.

Are you sure about this? Industry best practise is -- if possible, be 
backwards compatable; if that can't be done, provide an automatic 
updater. This has always been the case eg with Visual Basic.

It seems quite wreckless to update C while breaking existing programs and 
leaving people to re-code manually!

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#17620

From	Keith Thompson <kst-u@mib.org>
Date	2012-02-19 12:15 -0800
Message-ID	<lnk43ieg07.fsf@nuthaus.mib.org>
In reply to	#17617

Lord Voldermort <nospam@nospam.com> writes:
> Ben Bacarisse writes:
>> Lord Voldermort <nospam@nospam.com> writes: <snip>
>>> Thx for the info Keiht, sorry about breech of protocol - didnt see a
>>> way to tell how many ppl are in this room so didnt know whether it was
>>> empty or ppl just missed my post.
>> 
>> Have a read of this: http://en.wikipedia.org/wiki/Usenet to get an
>> overview.
>
> Didnt have time to read all that, but just flicking through I didnt see 
> anything about listing other people currently in this room/browsing the 
> forum/whatever you want to call it.

There is no such feature.  Don't think of this as a "room".  A closer
metaphor might be distributed broadcast e-mail that anyone can read and
write.

I read your article on my own computer; there is no central server
that would know that.  Your article was downloaded by the news
server I use (which happens to be news.eternal-september.org), but
that's just one of a number of news servers that share information
with each other.  News servers transmit articles back and forth;
they don't track users.  There is no central authority.

Usenet is older than the World Wide Web; early versions of it
didn't even use the Internet.  (Modern implementations use the
NNTP protocol over TCP/IP.)

Hang around for a while; you'll get the hang of it.

>>> So is there any translation program then to take code for the previous
>>> standard and upgrade it to work with C11 (replace gets by fgets etc)?
>> 
>> In a way, yes.  Your compiler can help if you if you ask for conformance
>> to a specific standard.  That is likely to flag up problems, but it
>> won't fix them, of course.  Some, like calls to gets, can't be fixed
>> automatically because the problem is that the function just does not
>> have enough information to do a safe job.  Each call needs to be looked
>> at by someone who understands the code.
>> 
>> If the code is very old (pre-C90, often called K&R C) you'd have to have
>> a good reason to update it because the move to prototypes alters the way
>> a function is called in subtle ways.  If in doubt, ask about that
>> specifically.
>
> Are you sure about this? Industry best practise is -- if possible, be 
> backwards compatable; if that can't be done, provide an automatic 
> updater. This has always been the case eg with Visual Basic.
>
> It seems quite wreckless to update C while breaking existing programs and 
> leaving people to re-code manually!

The gets() function in particular is inherently unsafe.  It should not
have been in the language in the first place, and programmers should
never have used it.  That's why it was removed from C11.  The only
programs that removing gets() might break were broken already, and those
programs *cannot* be fixed other than by manual recoding.

In any case, removing it from the standard doesn't magically remove it
from implementations.  Implementers are still free to provide it as an
extension, or simply because they haven't yet fully implemented C11
(most C compilers haven't fully implemented C99 yet).

Note that some implementations already issue warnings for calls to
gets() (this particular warning is from the GNU linker):

c.c:(.text+0x52): warning: the `gets' function is dangerous and should not be used.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#17629

From	Geoff <geoff@invalid.invalid>
Date	2012-02-19 13:58 -0800
Message-ID	<amr2k79f4vu7a5plhuuo8uonmh3eo9o1sh@4ax.com>
In reply to	#17617

On Sun, 19 Feb 2012 19:53:43 +0000 (UTC), Lord Voldermort
<nospam@nospam.com> wrote:

>It seems quite wreckless to update C while breaking existing programs and 
>leaving people to re-code manually!

Another aioe troll perhaps?

While it might be wreckless, it certainly isn't reckless to update the
C standard going forward. Revising the standard might break old
programs for compilation on new compilers but the medicine is more
beneficial than harmful.

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#17631

From	Stephen Sprunk <stephen@sprunk.org>
Date	2012-02-19 17:19 -0600
Message-ID	<jhs023$u48$1@dont-email.me>
In reply to	#17617

On 19-Feb-12 13:53, Lord Voldermort wrote:
> Ben Bacarisse writes:
>> Lord Voldermort <nospam@nospam.com> writes: <snip>
>>> Thx for the info Keiht, sorry about breech of protocol - didnt see a
>>> way to tell how many ppl are in this room so didnt know whether it was
>>> empty or ppl just missed my post.
>>
>> Have a read of this: http://en.wikipedia.org/wiki/Usenet to get an
>> overview.
> 
> Didnt have time to read all that,

Yet you're perfectly willing to waste dozens to thousands of potential
readers' time with your misunderstanding?  How rude of you.

> but just flicking through I didnt see anything about listing other
> people currently in this room/browsing the forum/whatever you want to
> call it.

That's because that's not how USENET works; it is not a live chat room.
 Your message (slowly) spreads from server to server around the world,
and those who are interested will read it when they get around to
checking for new messages on their server, which might be hours, days or
even years later.  Do not expect a response within minutes.

Incidentally, with modern threaded newsreaders, replying to your own
post does not "bump" it.  And failed attempts to do so are more likely
to make readers dismiss your question rather than help you, so don't do
that.

>>> So is there any translation program then to take code for the previous
>>> standard and upgrade it to work with C11 (replace gets by fgets etc)?
>>
>> In a way, yes.  Your compiler can help if you if you ask for conformance
>> to a specific standard.  That is likely to flag up problems, but it
>> won't fix them, of course.  Some, like calls to gets, can't be fixed
>> automatically because the problem is that the function just does not
>> have enough information to do a safe job.  Each call needs to be looked
>> at by someone who understands the code.
>>
>> If the code is very old (pre-C90, often called K&R C) you'd have to have
>> a good reason to update it because the move to prototypes alters the way
>> a function is called in subtle ways.  If in doubt, ask about that
>> specifically.
> 
> Are you sure about this? Industry best practise is -- if possible, be 
> backwards compatable; if that can't be done, provide an automatic 
> updater. This has always been the case eg with Visual Basic.

That has not been the case for any programming language I've used, but I
was never forced to deal with VB.

The usual model is that features are deprecated (meaning they still
work, but you shouldn't use them, and compilers may complain if you do)
for a version or two before being officially removed.

> It seems quite wreckless to update C while breaking existing programs and 
> leaving people to re-code manually!

ISO goes to great lengths to reduce the impact of this, and generally
only does so when the feature is so unsafe that leaving it in would be
more reckless than removing it.

Also, some compilers (eg. gcc) offer the ability to compile your program
according to a specific version of the standard, not just the latest
one.  So, if your program is "broken" by a newer version of the
standard, eg. C11, you can just tell the compiler to use an older one,
eg. C89 or C99.  You only need to fix your program if you want to take
advantage of the new features in the later version.

S

-- 
Stephen Sprunk         "God does not play dice."  --Albert Einstein
CCIE #3723         "God is an inveterate gambler, and He throws the
K5SSS        dice at every possible opportunity." --Stephen Hawking

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#17633

From	James Kuyper <jameskuyper@verizon.net>
Date	2012-02-19 18:41 -0500
Message-ID	<jhs1ag$3l7$1@dont-email.me>
In reply to	#17617

On 02/19/2012 02:53 PM, Lord Voldermort wrote:
> Ben Bacarisse writes:
...
>> Have a read of this: http://en.wikipedia.org/wiki/Usenet to get an
>> overview.
> 
> Didnt have time to read all that, but just flicking through I didnt see 
> anything about listing other people currently in this room/browsing the 
> forum/whatever you want to call it.

The key difference between usenet and anything that you could reasonably
call a "room" is that with a room, you have a conversation with other
people who are currently in the same room. If two people can't can't be
in the room at the same time, they can't talk. With usenet, each person
checks usenet at the time that is convenient for them, and posts
responses when and if they wish to. My impression is that most people
who monitor these groups regularly do so at least once per day, but you
should never count on people posting more frequently than that, nor at
the same time of day that you do, and particular people might miss a day.

As a result, usenet conversations can be a lot slower than they are in
anything that relies on a "room" metaphor. I recently noticed someone
who'd been away for a long time posting a flurry of responses to other
people's messages, in many cases more than a month old. That's a bit
extreme, but I didn't notice anybody complain about it. In general,
people don't seem to start complaining until the message you're replying
to is at least several months old.

...
>> If the code is very old (pre-C90, often called K&R C) you'd have to have
>> a good reason to update it because the move to prototypes alters the way
>> a function is called in subtle ways.  If in doubt, ask about that
>> specifically.
> 
> Are you sure about this? Industry best practise is -- if possible, be 
> backwards compatable; if that can't be done, provide an automatic 
> updater. This has always been the case eg with Visual Basic.
> 
> It seems quite wreckless to update C while breaking existing programs and 
> leaving people to re-code manually!

Backwards compatibility is very important to the C committee. If you
monitor this newsgroup long enough, you'll discover that in the opinions
of several people posting here (not including me) the committee pays far
too much attention to backwards compatibility.

A key point to remember is that K&R C was not standardized - there were
many different versions of C floating around, most of them incompatible
with each other to varying degrees. When the C standard came out, it
maintained a degree of backwards compatibility by letting many things be
unspecified, or implementation-defined, or have undefined behavior - but
they also necessarily broke backwards compatibility with many (perhaps
most) pre-standard compilers by specifically defining a great many
things. When a compiler came out with a new version that fully conformed
to the standard, some code necessarily had to be be re-written to work
with the conforming version, but a great deal did not have to be
re-written, because of the things the standard left unspecified or
undefined, which the compiler was therefore free to continue handling
the same way it always had.

Again, you'll find people posting to this newsgroup who object
strenuously to those decisions, preferring that the standard break
backwards compatibility more thoroughly than it did, by specifying
everything, and leaving nothing undefined. I can sympathize with that
desire, but it would have prevented implementation of C on any platform,
past, present or future, for which those decisions were incompatible
with efficient implementation of C.
-- 
James Kuyper

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#17637

From	Robert Wessel <robertwessel2@yahoo.com>
Date	2012-02-20 01:51 -0600
Message-ID	<mgu3k7l7falujvpao1n77v0hb32ggfbfdf@4ax.com>
In reply to	#17617

On Sun, 19 Feb 2012 19:53:43 +0000 (UTC), Lord Voldermort
<nospam@nospam.com> wrote:

>Ben Bacarisse writes:
>> Lord Voldermort <nospam@nospam.com> writes: <snip>
>> 
>>> Thx for the info Keiht, sorry about breech of protocol - didnt see a
>>> way to tell how many ppl are in this room so didnt know whether it was
>>> empty or ppl just missed my post.
>> 
>> Have a read of this: http://en.wikipedia.org/wiki/Usenet to get an
>> overview.
>
>Didnt have time to read all that, but just flicking through I didnt see 
>anything about listing other people currently in this room/browsing the 
>forum/whatever you want to call it.
>
>>> So is there any translation program then to take code for the previous
>>> standard and upgrade it to work with C11 (replace gets by fgets etc)?
>> 
>> In a way, yes.  Your compiler can help if you if you ask for conformance
>> to a specific standard.  That is likely to flag up problems, but it
>> won't fix them, of course.  Some, like calls to gets, can't be fixed
>> automatically because the problem is that the function just does not
>> have enough information to do a safe job.  Each call needs to be looked
>> at by someone who understands the code.
>> 
>> If the code is very old (pre-C90, often called K&R C) you'd have to have
>> a good reason to update it because the move to prototypes alters the way
>> a function is called in subtle ways.  If in doubt, ask about that
>> specifically.
>
>Are you sure about this? Industry best practise is -- if possible, be 
>backwards compatable; if that can't be done, provide an automatic 
>updater. This has always been the case eg with Visual Basic.
>
>It seems quite wreckless to update C while breaking existing programs and 
>leaving people to re-code manually!


You've misunderstood Ben.  The addition of function prototypes in the
language did not break existing programs.  What may cause somewhat
subtle problems if you change your K&R style function declarations to
prototypes.  There are case where the obvious prototype will cause
somewhat different behavior, and cases where the exact behavior cannot
be matched at all (although such are usually indicative of other
problems).  But you can just leave your K&R style declarations as-is,
and nothing breaks.

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#17644

From	Keith Thompson <kst-u@mib.org>
Date	2012-02-20 02:19 -0800
Message-ID	<ln39a5erhs.fsf@nuthaus.mib.org>
In reply to	#17637

Robert Wessel <robertwessel2@yahoo.com> writes:
> On Sun, 19 Feb 2012 19:53:43 +0000 (UTC), Lord Voldermort
> <nospam@nospam.com> wrote:
[...]
>>Are you sure about this? Industry best practise is -- if possible, be 
>>backwards compatable; if that can't be done, provide an automatic 
>>updater. This has always been the case eg with Visual Basic.
>>
>>It seems quite wreckless to update C while breaking existing programs and 
>>leaving people to re-code manually!
>
> You've misunderstood Ben.  The addition of function prototypes in the
> language did not break existing programs.  What may cause somewhat
> subtle problems if you change your K&R style function declarations to
> prototypes.  There are case where the obvious prototype will cause
> somewhat different behavior, and cases where the exact behavior cannot
> be matched at all (although such are usually indicative of other
> problems).  But you can just leave your K&R style declarations as-is,
> and nothing breaks.

Not quite.

Non-prototype declarations are still in the language, up to and
including the 2011 standard (and have been obsolescent since C89).
But C99 removed implicit int, which did break existing code
(though the fix was straightforward and fixed code could still be
compatible with pre-ANSI compilers).  C11's removal of gets() also
broke existing code (though such code was already arguably broken).

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#17640

From	Nick Keighley <nick_keighley_nospam@hotmail.com>
Date	2012-02-20 00:45 -0800
Message-ID	<44e03f36-ab00-4cbd-962b-d35ed8516686@t24g2000yqj.googlegroups.com>
In reply to	#17602

On Feb 19, 10:54 am, Lord Voldermort <nos...@nospam.com> wrote:

> Thx

try to avoid text-speak

> for the info Keiht,

try to spell peoples' names correctly

> sorry about breech of protocol

that's "breach"- your spelling refers to trousers

> - didnt see a way
> to tell how many ppl are in this room

it isn't a room it's a usenet group

> so didnt know whether it was empty
> or ppl just missed my post.

<snip>

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#17641

From	Nick Keighley <nick_keighley_nospam@hotmail.com>
Date	2012-02-20 00:52 -0800
Message-ID	<bd3798a2-90a4-4be6-a2c4-d097594f100a@b23g2000yqn.googlegroups.com>
In reply to	#17602

On Feb 19, 10:54 am, Lord Voldermort <nos...@nospam.com> wrote:

> So is there any translation program then to take code for the previous
> standard and upgrade it to work with C11 (replace gets by fgets etc)?

fgets() isn't a straight replacement for gets(). The end-of-line
handling is different. I also suspect the "translation program" would
have to read your mind in some cases in order to get the buffer size
right for fgets(). Do you use gets() a lot, or use programs that do?

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#17658

From	Ben Bacarisse <ben.usenet@bsb.me.uk>
Date	2012-02-20 13:25 +0000
Message-ID	<0.ee91c1f1976309150aa7.20120220132552GMT.87k43htz4v.fsf@bsb.me.uk>
In reply to	#17641

Nick Keighley <nick_keighley_nospam@hotmail.com> writes:

> On Feb 19, 10:54 am, Lord Voldermort <nos...@nospam.com> wrote:
>
>> So is there any translation program then to take code for the previous
>> standard and upgrade it to work with C11 (replace gets by fgets etc)?
>
> fgets() isn't a straight replacement for gets(). The end-of-line
> handling is different. I also suspect the "translation program" would
> have to read your mind in some cases in order to get the buffer size
> right for fgets(). Do you use gets() a lot, or use programs that do?

If you simply must get your gets-containing code to run today, you can use:

#define gets(s) (scanf("%[^\n]%*c", (s)) == 1 ? (s) : NULL)

but you should fix it tomorrow!  (Not you personally, of course, but
"one" is sometimes too formal for Usenet).

-- 
Ben.

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#17682

From	Keith Thompson <kst-u@mib.org>
Date	2012-02-20 10:33 -0800
Message-ID	<lnty2lcq2l.fsf@nuthaus.mib.org>
In reply to	#17658

Ben Bacarisse <ben.usenet@bsb.me.uk> writes:
> Nick Keighley <nick_keighley_nospam@hotmail.com> writes:
>> On Feb 19, 10:54 am, Lord Voldermort <nos...@nospam.com> wrote:
>>> So is there any translation program then to take code for the previous
>>> standard and upgrade it to work with C11 (replace gets by fgets etc)?
>>
>> fgets() isn't a straight replacement for gets(). The end-of-line
>> handling is different. I also suspect the "translation program" would
>> have to read your mind in some cases in order to get the buffer size
>> right for fgets(). Do you use gets() a lot, or use programs that do?
>
> If you simply must get your gets-containing code to run today, you can use:
>
> #define gets(s) (scanf("%[^\n]%*c", (s)) == 1 ? (s) : NULL)
>
> but you should fix it tomorrow!  (Not you personally, of course, but
> "one" is sometimes too formal for Usenet).

If you simply must get such code running *today*, you can just
leave the gets() call in place.  I don't believe there are yet any
hosted C implementations that don't provide it.

-- 
Keith Thompson (The_Other_Keith) kst-u@mib.org  <http://www.ghoti.net/~kst>
    Will write code for food.
"We must do something.  This is something.  Therefore, we must do this."
    -- Antony Jay and Jonathan Lynn, "Yes Minister"

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#17747

From	Quentin Pope <qp19433@hotmail.NOSPAM.com>
Date	2012-02-21 19:51 +0000
Message-ID	<ji0skh$7lc$1@speranza.aioe.org>
In reply to	#17658

On Mon, 20 Feb 2012 13:25:52 +0000, Ben Bacarisse wrote:
> Nick Keighley <nick_keighley_nospam@hotmail.com> writes:
> 
>> On Feb 19, 10:54 am, Lord Voldermort <nos...@nospam.com> wrote:
>>
>>> So is there any translation program then to take code for the previous
>>> standard and upgrade it to work with C11 (replace gets by fgets etc)?
>>
>> fgets() isn't a straight replacement for gets(). The end-of-line
>> handling is different. I also suspect the "translation program" would
>> have to read your mind in some cases in order to get the buffer size
>> right for fgets(). Do you use gets() a lot, or use programs that do?
> 
> If you simply must get your gets-containing code to run today, you can
> use:
> 
> #define gets(s) (scanf("%[^\n]%*c", (s)) == 1 ? (s) : NULL)
> 
> but you should fix it tomorrow!  (Not you personally, of course, but
> "one" is sometimes too formal for Usenet).

Does that mean that the identifier gets has been returned to the user's 
namespace? That sounds like a recipe for confusion if people try to mix 
old code with C11 code that uses gets for something unrelated to the  
original function.

//QP

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#17748

From	James Kuyper <jameskuyper@verizon.net>
Date	2012-02-21 15:11 -0500
Message-ID	<4F43FA5F.2060507@verizon.net>
In reply to	#17747

On 02/21/2012 02:51 PM, Quentin Pope wrote:
...
> Does that mean that the identifier gets has been returned to the user's 
> namespace? ...

Yes. In the new standard, gets() is only mentioned in two places:
Forward: as something that has been removed.
Footnote 440: as something to compare gets_s() to.

Therefore, it is no longer counts as one of the identifier referred to
by 7.1.3p1.

> ... That sounds like a recipe for confusion if people try to mix 
> old code with C11 code that uses gets for something unrelated to the  
> original function.

True, but all of the other reserved identifiers are either generically
reserved to implementation for certain purposes, specifically reserved
for current standard-defined uses, or specifically reserved in
anticipation of future standard-defined uses. There's no precedent for
adding a specific obsolete identifier to the reserved list - and this
version of the standard establishes a precedent for not doing so.

For the next decade or two, any decent C2011+ compiler will probably
have an option that warns about user-provided definitions of 'gets', but
I wouldn't recommend counting on that in the long-term.

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csiph-web

Has Implicit Int been disabled in the new C11 standard? What about other previously depreciated constructions eg gets?

Contents

#17583 — Has Implicit Int been disabled in the new C11 standard? What about other previously depreciated constructions eg gets?

#17584

#17585

#17599

#17586

#17602

#17603

#17617

#17620

#17629

#17631

#17633

#17637

#17644

#17640

#17641

#17658

#17682

#17747

#17748