Re: standard error messages in a std::string or in a const char *

From	Soviet_Mario <SovietMario@CCCP.MIR>
Newsgroups	comp.lang.c++
Subject	Re: standard error messages in a std::string or in a const char *
Date	2019-09-11 17:43 +0200
Organization	A noiseless patient Spider
Message-ID	<qlb4o0$m6s$1@dont-email.me> (permalink)
References	<ql98g2$8tf$1@dont-email.me> <ql98je$8tf$2@dont-email.me> <slrnqnhc2b.cdo.grahn+nntp@frailea.sa.invalid> <qlacv3$1d1o$1@adenine.netfront.net>

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Il 11/09/19 10:58, Juha Nieminen ha scritto:
> Jorgen Grahn <grahn+nntp@snipabacken.se> wrote:
>>> https://linux.die.net/man/3/strerror
>>>
>>> maybe will work ...
>>
>> It will do what the documentation says, and lots of people use it.
>> Note its limitations, though.  It's not thread-safe, for example.
> 
> What do you mean it's not thread-safe? AFAIK errno is thread-local
> according to the standard.
> 

maybe errno is such, but I think strerror should return a 
pointer to an internal buffer which it alone reserves the 
right to modify on subsequent calls.
In this buffer the function should copy the message (or 
maybe it just sets the pointer to a more risky internally 
maintained table ... much faster).

So if different threads calls the functions without notice, 
one thread could get the error generated from the other ...
That's the little I have understood

but my main problem is : even including all possible 
headers, QT IDE does not see strerror prototype.

Normally when I include sth, within seconds the intellisense 
starts popping up the parameters type-info and return value. 
Here it does not do so, and underlines the name in red as 
unknown :\ :\

-- 
1) Resistere, resistere, resistere.
2) Se tutti pagano le tasse, le tasse le pagano tutti
Soviet_Mario - (aka Gatto_Vizzato)

Thread

standard error messages in a std::string or in a const char * Soviet_Mario <SovietMario@CCCP.MIR> - 2019-09-11 00:35 +0200
  Re: standard error messages in a std::string or in a const char * Soviet_Mario <SovietMario@CCCP.MIR> - 2019-09-11 00:37 +0200
    Re: standard error messages in a std::string or in a const char * Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-09-11 08:28 +0000
      Re: standard error messages in a std::string or in a const char * Juha Nieminen <nospam@thanks.invalid> - 2019-09-11 08:58 +0000
        Re: standard error messages in a std::string or in a const char * Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-11 11:09 +0200
          Re: standard error messages in a std::string or in a const char * Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-11 11:37 +0200
        Re: standard error messages in a std::string or in a const char * Keith Thompson <kst-u@mib.org> - 2019-09-11 02:37 -0700
          Re: standard error messages in a std::string or in a const char * Bonita Montero <Bonita.Montero@gmail.com> - 2019-09-11 11:47 +0200
            Re: standard error messages in a std::string or in a const char * Öö Tiib <ootiib@hot.ee> - 2019-09-11 04:43 -0700
              Re: standard error messages in a std::string or in a const char * James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-11 08:27 -0400
                Re: standard error messages in a std::string or in a const char * Manfred <noname@add.invalid> - 2019-09-11 14:56 +0200
                Re: standard error messages in a std::string or in a const char * Daniel <danielaparker@gmail.com> - 2019-09-11 07:00 -0700
          Re: standard error messages in a std::string or in a const char * Thiago Adams <thiago.adams@gmail.com> - 2019-09-11 09:44 -0700
          Re: standard error messages in a std::string or in a const char * Jorgen Grahn <grahn+nntp@snipabacken.se> - 2019-09-12 10:21 +0000
            Re: standard error messages in a std::string or in a const char * Soviet_Mario <SovietMario@CCCP.MIR> - 2019-09-12 13:05 +0200
        Re: standard error messages in a std::string or in a const char * Soviet_Mario <SovietMario@CCCP.MIR> - 2019-09-11 17:43 +0200
          Re: standard error messages in a std::string or in a const char * Paavo Helde <myfirstname@osa.pri.ee> - 2019-09-11 19:23 +0300
            Re: standard error messages in a std::string or in a const char * Soviet_Mario <SovietMario@CCCP.MIR> - 2019-09-11 19:19 +0200
              Re: standard error messages in a std::string or in a const char * Paavo Helde <myfirstname@osa.pri.ee> - 2019-09-11 20:32 +0300
                Re: standard error messages in a std::string or in a const char * Soviet_Mario <SovietMario@CCCP.MIR> - 2019-09-12 13:08 +0200
                Re: standard error messages in a std::string or in a const char * Thiago Adams <thiago.adams@gmail.com> - 2019-09-12 04:29 -0700
                Re: standard error messages in a std::string or in a const char * Keith Thompson <kst-u@mib.org> - 2019-09-12 14:41 -0700
              Re: standard error messages in a std::string or in a const char * Thiago Adams <thiago.adams@gmail.com> - 2019-09-11 10:39 -0700
              Re: standard error messages in a std::string or in a const char * James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-11 19:50 -0400
                Re: standard error messages in a std::string or in a const char * Keith Thompson <kst-u@mib.org> - 2019-09-11 17:11 -0700
                Re: standard error messages in a std::string or in a const char * James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-11 20:23 -0400
                Re: standard error messages in a std::string or in a const char * David Brown <david.brown@hesbynett.no> - 2019-09-12 11:21 +0200
                Re: standard error messages in a std::string or in a const char * James Kuyper <jameskuyper@alumni.caltech.edu> - 2019-09-12 07:31 -0400
                Re: standard error messages in a std::string or in a const char * Manfred <noname@add.invalid> - 2019-09-12 15:44 +0200

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