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Re: recovering from std::bad_alloc in std::string reserve

From Lynn McGuire <lynnmcguire5@gmail.com>
Newsgroups comp.lang.c++
Subject Re: recovering from std::bad_alloc in std::string reserve
Date 2021-05-26 13:32 -0500
Organization A noiseless patient Spider
Message-ID <s8m48i$g6f$3@dont-email.me> (permalink)
References <s8hkt2$liv$1@dont-email.me> <s8lt9d$tf0$1@dont-email.me>

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On 5/26/2021 11:33 AM, Alf P. Steinbach wrote:
> On 2021-05-25 03:46, Lynn McGuire wrote:
>> I am getting std::bad_alloc from the following code when I try to 
>> reserve a std::string of size 937,180,144:
>>
>> std::string filename = getFormsMainOwner () -> getOutputFileName ();
>> FILE * pOutputFile = nullptr;
>> errno_t err = fopen_s_UTF8 ( & pOutputFile, filename.c_str (), "rt");
>> if (err == 0)
>> {
>>      std::string outputFileBuffer;
>>          //  need to preallocate the space in case the output file is 
>> a gigabyte or more, PMR 6408
>>      fseek (pOutputFile, 0, SEEK_END);
>>      size_t outputFileLength = ftell (pOutputFile) + 42;  // give it 
>> some slop
>>      fseek (pOutputFile, 0, SEEK_SET);
>>      outputFileBuffer.reserve (outputFileLength);
> 
> [snip]
> 
> In the above code `ftell` will fail in Windows if the file is 2GB or 
> more, because in Windows, even in 64-bit Windows, the `ftell` return 
> type `long` is just 32 bits.
> 
> However, the C++ level iostreams can report the file size correctly:
> 
> 
> ---------------------------------------------------------------------------- 
> 
> #include <stdio.h>      // fopen, fseek, ftell, fclose
> #include <stdlib.h>     // EXIT_...
> 
> #include <iostream>
> #include <fstream>
> #include <stdexcept>        // runtime_error
> using namespace std;
> 
> auto hopefully( const bool e ) -> bool { return e; }
> auto fail( const char* s ) -> bool { throw runtime_error( s ); }
> 
> struct Is_zero {};
> auto operator>>( int x, Is_zero ) -> bool { return x == 0; }
> 
> const auto& filename = "large_file";
> 
> void c_level_check()
> {
>      struct C_file
>      {
>          FILE* handle;
>          ~C_file() { if( handle != 0 ) { fclose( handle ); } }
>      };
> 
>      auto const f = C_file{ fopen( ::filename, "rb" ) };
>      hopefully( !!f.handle )
>          or fail( "fopen failed" );
>      fseek( f.handle, 0, SEEK_END )
>          >> Is_zero()
>          or fail( "fseek failed, probably rather biggus filus" );
>      const long pos = ftell( f.handle );
>      hopefully( pos >= 0 )
>          or fail( "ftell failed" );
>      cout << "`ftell` says the file is " << pos << " byte(s)." << endl;
> }
> 
> void cpp_level_check()
> {
>      auto f = ifstream( ::filename, ios::in | ios::binary );
>      f.seekg( 0, ios::end );
>      const ifstream::pos_type pos = f.tellg();
>      hopefully( pos != -1 )
>          or fail( "ifstream::tellg failed" );
>      cout << "`ifstream::tellg` says the file is " << pos << " bytes." 
> << endl;
> }
> 
> void cpp_main()
> {
>      try {
>          c_level_check();
>      } catch( const exception& x ) {
>          cerr << "!" << x.what() << endl;
>          cpp_level_check();
>      }
> }
> 
> auto main() -> int
> {
>      try {
>          cpp_main();
>          return EXIT_SUCCESS;
>      } catch( const exception& x ) {
>          cerr << "!" << x.what() << endl;
>      }
>      return EXIT_FAILURE;
> }
> ------------------------------------------------------------------------------- 
> 
> 
> When I tested this with `large_file` as a copy of the roughly 4GB 
> "Bad.Boys.for.Life.2020.1080p.WEB-DL.DD5.1.H264-FGT.mkv", I got
> 
> 
> [c:\root\dev\explore\filesize]
>  > b
> !ftell failed
> `ifstream::tellg` says the file is 4542682554 bytes.
> 
> 
> - Alf

I have already replaced the fell code with _ftelli64.

//  get the size of the output file
fseek (pOutputFile, 0, SEEK_END);
__int64 outputFileLength = _ftelli64 (pOutputFile) + 42;  // give it 
some slop
int outputFileLengthInt = (int) outputFileLength;
fseek (pOutputFile, 0, SEEK_SET);

Thanks,
Lynn

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Thread

recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-24 20:46 -0500
  Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-24 20:50 -0500
    Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-24 20:52 -0500
      Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-25 07:47 +0300
        Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-25 12:20 -0500
          Re: recovering from std::bad_alloc in std::string reserve Christian Gollwitzer <auriocus@gmx.de> - 2021-05-26 08:36 +0200
            Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-26 13:28 -0500
      Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-25 12:56 +0200
        Re: recovering from std::bad_alloc in std::string reserve scott@slp53.sl.home (Scott Lurndal) - 2021-05-25 14:55 +0000
          Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-25 18:42 +0300
            Re: recovering from std::bad_alloc in std::string reserve MrSpook_Ann1u@d0v_5eh1bqgd.com - 2021-05-25 16:10 +0000
              Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-25 18:23 +0200
              Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-25 19:57 +0300
                Re: recovering from std::bad_alloc in std::string reserve MrSpook_ddZgr4t4@okc9_pd48oig5.info - 2021-05-26 07:15 +0000
                Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-26 09:22 +0200
                Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-26 10:54 +0300
                Re: recovering from std::bad_alloc in std::string reserve MrSpook_dw5lvA4g@kak0_42x.edu - 2021-05-26 08:29 +0000
            Re: recovering from std::bad_alloc in std::string reserve Nikolaj Lazic <nlazicBEZ_OVOGA@mudrac.ffzg.hr> - 2021-05-25 16:21 +0000
              Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-25 20:04 +0300
                Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-25 12:46 -0500
                Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-25 20:58 +0300
                Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-25 13:48 -0500
                Re: recovering from std::bad_alloc in std::string reserve Nikolaj Lazic <nlazicBEZ_OVOGA@mudrac.ffzg.hr> - 2021-05-25 18:23 +0000
                Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-25 13:49 -0500
                Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-26 21:07 -0500
          Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-25 18:23 +0200
  Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-24 22:33 -0500
    Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-24 22:35 -0500
      Re: recovering from std::bad_alloc in std::string reserve Juha Nieminen <nospam@thanks.invalid> - 2021-05-25 05:16 +0000
        Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-25 13:00 +0200
        Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-25 12:49 -0500
  Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-27 14:08 -0500
    Re: recovering from std::bad_alloc in std::string reserve scott@slp53.sl.home (Scott Lurndal) - 2021-05-27 21:59 +0000
      Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-05-27 15:33 -0700
        Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-05-27 15:58 -0700
          Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-27 18:17 -0500
            Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-05-27 16:58 -0700
              Re: recovering from std::bad_alloc in std::string reserve Öö Tiib <ootiib@hot.ee> - 2021-05-27 18:36 -0700
                Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-27 21:38 -0500
                Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-28 08:53 +0300
                Re: recovering from std::bad_alloc in std::string reserve Bo Persson <bo@bo-persson.se> - 2021-05-28 09:47 +0200
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-05-27 19:54 -0700
                Re: recovering from std::bad_alloc in std::string reserve Öö Tiib <ootiib@hot.ee> - 2021-05-27 21:02 -0700
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-05-28 12:09 -0700
                Re: recovering from std::bad_alloc in std::string reserve scott@slp53.sl.home (Scott Lurndal) - 2021-05-28 20:26 +0000
                Re: recovering from std::bad_alloc in std::string reserve Öö Tiib <ootiib@hot.ee> - 2021-05-28 17:10 -0700
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-05-29 11:47 +0200
                Re: recovering from std::bad_alloc in std::string reserve "daniel...@gmail.com" <danielaparker@gmail.com> - 2021-05-30 15:15 -0700
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-05-31 08:33 +0200
                Re: recovering from std::bad_alloc in std::string reserve "daniel...@gmail.com" <danielaparker@gmail.com> - 2021-05-31 08:21 -0700
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-05-31 18:13 +0200
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-05-31 14:43 -0700
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-05-31 14:44 -0700
                Re: recovering from std::bad_alloc in std::string reserve "daniel...@gmail.com" <danielaparker@gmail.com> - 2021-05-31 15:20 -0700
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-06-01 11:17 -0700
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-01 20:25 +0200
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-06-01 16:55 -0700
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-02 09:06 +0200
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-06-05 17:50 -0700
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-06 11:10 +0200
                Re: recovering from std::bad_alloc in std::string reserve Öö Tiib <ootiib@hot.ee> - 2021-06-06 04:07 -0700
                Re: recovering from std::bad_alloc in std::string reserve Richard Damon <Richard@Damon-Family.org> - 2021-06-06 07:49 -0400
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-01 20:21 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-02 09:29 +0200
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-02 18:43 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-02 23:32 +0200
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-03 00:49 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-03 09:08 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-03 10:53 +0200
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-03 16:20 +0200
                Re: recovering from std::bad_alloc in std::string reserve James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-06-03 11:20 -0400
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-03 19:04 +0200
                Re: recovering from std::bad_alloc in std::string reserve scott@slp53.sl.home (Scott Lurndal) - 2021-06-03 22:24 +0000
                Re: recovering from std::bad_alloc in std::string reserve Öö Tiib <ootiib@hot.ee> - 2021-06-03 16:27 -0700
                Re: recovering from std::bad_alloc in std::string reserve scott@slp53.sl.home (Scott Lurndal) - 2021-06-04 00:36 +0000
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-04 08:46 +0200
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-06-05 22:02 -0700
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-06 11:17 +0200
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-06 18:39 +0200
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-06-06 16:33 -0700
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-07 08:41 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-06 17:46 +0200
                Re: recovering from std::bad_alloc in std::string reserve MrSpook_Qfmtjdmi@nc6.com - 2021-06-06 14:11 +0000
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-03 16:43 +0200
                Re: recovering from std::bad_alloc in std::string reserve Manfred <noname@add.invalid> - 2021-06-01 18:00 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-01 19:15 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-01 15:55 +0200
                Re: recovering from std::bad_alloc in std::string reserve Bo Persson <bo@bo-persson.se> - 2021-06-01 13:59 +0200
                Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-06-01 13:26 -0500
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-01 08:29 +0200
                Re: recovering from std::bad_alloc in std::string reserve Bo Persson <bo@bo-persson.se> - 2021-06-01 14:05 +0200
                Re: recovering from std::bad_alloc in std::string reserve David Brown <david.brown@hesbynett.no> - 2021-06-01 15:58 +0200
                Re: recovering from std::bad_alloc in std::string reserve James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-06-01 11:33 -0400
                Re: recovering from std::bad_alloc in std::string reserve Keith Thompson <Keith.S.Thompson+u@gmail.com> - 2021-06-01 10:52 -0700
            Re: recovering from std::bad_alloc in std::string reserve James Kuyper <jameskuyper@alumni.caltech.edu> - 2021-05-27 23:16 -0400
            Re: recovering from std::bad_alloc in std::string reserve scott@slp53.sl.home (Scott Lurndal) - 2021-05-28 14:34 +0000
          Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-27 18:19 -0500
        Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-28 03:47 +0200
      Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-27 17:45 -0500
        Re: recovering from std::bad_alloc in std::string reserve scott@slp53.sl.home (Scott Lurndal) - 2021-05-28 14:38 +0000
          Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-28 16:44 +0200
          Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-28 16:42 +0200
          Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-28 18:22 +0300
      Re: recovering from std::bad_alloc in std::string reserve Paavo Helde <myfirstname@osa.pri.ee> - 2021-05-28 08:47 +0300
  Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-26 06:16 +0200
    Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-26 13:30 -0500
      Re: recovering from std::bad_alloc in std::string reserve Bonita Montero <Bonita.Montero@gmail.com> - 2021-05-26 20:37 +0200
        Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-26 14:09 -0500
  Re: recovering from std::bad_alloc in std::string reserve "Alf P. Steinbach" <alf.p.steinbach@gmail.com> - 2021-05-26 18:33 +0200
    Re: recovering from std::bad_alloc in std::string reserve Lynn McGuire <lynnmcguire5@gmail.com> - 2021-05-26 13:32 -0500
      Re: recovering from std::bad_alloc in std::string reserve Christian Gollwitzer <auriocus@gmx.de> - 2021-05-27 07:50 +0200
  Re: recovering from std::bad_alloc in std::string reserve "Chris M. Thomasson" <chris.m.thomasson.1@gmail.com> - 2021-06-01 17:35 -0700

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