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903 :: [BUG?] echo vs write(stdout)

• axben (orginal) [2015-02-20T13:59:21+01:00] view original

  Considering the output of

  let OUT = " ■ "   # U+25A0, file stored in UTF-8 format
  for i in 0..5: echo OUT
  for i in 0..5: write(stdout, OUT)
  Run

  under Windows 7 (64 bit, CP65001), is the exception sth. I should expect?

  Is there an echo() w/o linefeed btw. (didn't find it though...)?

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• OderWat (orginal) [2015-02-20T14:05:58+01:00] view original

  As it works on OS X I guess that is unexpected!?

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• axben (orginal) [2015-02-20T15:39:11+01:00] view original

  One cannot compare Linux/Mac OS X with Windows when it comes to UTF-8 output, as there are too many differences. So the fact that it is working there doesn't come at a surprise ;-)

  Wat nu?

  EDIT: The point is echo(...) which supposedly should be sth. like write(stdout, ...) works differently as I would expect it (the latter command even crashes). If however write(stdout, ...) isn't echo(...) w/o the linefeed, what is it's write() counterpart (or vice versa)?

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• OderWat (orginal) [2015-02-20T18:50:04+01:00] view original

  Did you look in the generated code? On OS X (and yes I know they work differently) I get basically the following:

  {
                  NI res_88025;
                  res_88025 = 0;
                  {
                          while (1) {
                                  if (!(res_88025 <= 5)) goto LA4;
                                  i_88017 = res_88025;
                                  printf("%s\012", out_88003? (out_88003)->data:"nil");
                                  res_88025 += 1;
                          } LA4: ;
                  }
          }
          {
                  NI res_88055;
                  res_88055 = 0;
                  {
                          while (1) {
                                  if (!(res_88055 <= 5)) goto LA7;
                                  i_88049 = res_88055;
                                  write_13261(stdout, out_88003);
                                  res_88055 += 1;
                          } LA7: ;
                  }
          }
  Run

  So it is just using printf. But I guess that will be the same on windows and that this does some magic? Which would mean you could at least resort to call printf from Nim?

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• axben (orginal) [2015-02-20T23:39:11+01:00] view original

  Running this code:

  let OUT = "[■]"   # U+25A0, file stored in UTF-8 format
  echo OUT
  write(stdout, OUT)
  Run

  gives me:

  
  [■]
  [■]Traceback (most recent call last)
  test2.nim(4)             test2
  system.nim(2239)         raiseEIO
  Error: unhandled exception: cannot write string to file [IOError]
  Run

  Please note the last line.

  Compiling the following C code (as extracted from the generated C source test2.c):

  #include <stdio.h>
  
  char *OUT = "[■]";   // U+25A0, file stored in UTF-8 format
  
  void main() {
     printf("%s\n", OUT);
     fwrite(OUT, 1, 5, stdout);
  }
  Run

  gives me (CP 65001 active):

  
  [■]
  [■]
  Run

  So, it seems the general setup (using printf/fwrite) is correct. There must be something wrong after fwrite().

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