[windows] file_write: require a console, not just a character device - #1374
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[windows] file_write: require a console, not just a character device#1374dimensionscape wants to merge 1 commit into
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_isatty is true for any character device, so a write to NUL took the
WriteConsoleW path. WriteConsoleW fails on a non-console handle and the
file_error after it throws from inside a GC-free zone, so the process dies
instead of reporting anything:
sys.io.File.write("NUL").writeString("x")
prog.exe >NUL
GetConsoleMode only succeeds on a real console, and __hxcpp_print already uses
it. _isatty stays as the first check so files and pipes take the same fwrite
path they did before.
Came in with 1544ff5 (HaxeFoundation#1307), which fixed utf console output. That part is
unchanged here.
tobil4sk
reviewed
Sep 2, 2026
| // _isatty is true for ANY character device - NUL, a serial port, a printer - and none of | ||
| // those accept WriteConsoleW. Only a real console has a console mode. | ||
| DWORD console_mode; | ||
| if (_isatty(_fileno(f->io)) && GetConsoleMode((HANDLE)_get_osfhandle(_fileno(f->io)), &console_mode)) { |
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Should we keep the _isatty check here? can we just rely on GetConsoleMode?
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_isatty is true for any character device, so a write to NUL took the WriteConsoleW path. WriteConsoleW fails on a non-console handle and the file_error after it throws from inside a GC-free zone, so the process dies instead of reporting anything:
GetConsoleMode only succeeds on a real console, and __hxcpp_print already uses it. _isatty stays as the first check so files and pipes take the same fwrite path they did before.
Came in with 1544ff5 (#1307), which fixed utf console output. That part is unchanged here.