[browser][MT] emscripten_check_mailbox per console character

[pavelsavara]

Console.WriteLine on non-UI thread would lead to cross thread message per character.

put_char (dotnet.native.js:1268)
write (dotnet.native.js:1216)
write (dotnet.native.js:2689)
doWritev (dotnet.native.js:5939)
_fd_write (dotnet.native.js:6012)
_emscripten_receive_on_main_thread_js (dotnet.native.js:5746)
_do_call (library_pthread.c:193)
em_task_queue_execute (em_task_queue.c:176)
receive_notification (em_task_queue.c:218)
em_task_queue_execute (em_task_queue.c:176)
_emscripten_check_mailbox (thread_mailbox.c:87)
(anonymous) (dotnet.native.js:744)
(anonymous) (dotnet.native.js:5475)
callUserCallback (dotnet.native.js:5452)
checkMailbox (dotnet.native.js:5475)

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Issue Details

---

Console.WriteLine on non-UI thread would lead to cross thread message per character.

put_char (dotnet.native.js:1268)
write (dotnet.native.js:1216)
write (dotnet.native.js:2689)
doWritev (dotnet.native.js:5939)
_fd_write (dotnet.native.js:6012)
_emscripten_receive_on_main_thread_js (dotnet.native.js:5746)
_do_call (library_pthread.c:193)
em_task_queue_execute (em_task_queue.c:176)
receive_notification (em_task_queue.c:218)
em_task_queue_execute (em_task_queue.c:176)
_emscripten_check_mailbox (thread_mailbox.c:87)
(anonymous) (dotnet.native.js:744)
(anonymous) (dotnet.native.js:5475)
callUserCallback (dotnet.native.js:5452)
checkMailbox (dotnet.native.js:5475)

Author:	pavelsavara
Assignees:	pavelsavara
Labels:	arch-wasm, area-System.Runtime.InteropServices.JavaScript, os-browser
Milestone:	9.0.0

[pavelsavara]

Other proxies functions are

var proxiedFunctionTable = [ 
null, 
_proc_exit, 
exitOnMainThread, 
pthreadCreateProxied, 
___syscall__newselect, 
___syscall_accept4, 
___syscall_bind, 
___syscall_chdir, 
___syscall_chmod, 
___syscall_connect, 
___syscall_faccessat, 
___syscall_fchmod, 
___syscall_fcntl64, 
___syscall_fstat64, 
___syscall_fstatfs64, 
___syscall_statfs64, 
___syscall_ftruncate64, 
___syscall_getcwd, 
___syscall_getdents64, 
___syscall_getsockname, 
___syscall_ioctl, 
___syscall_listen, 
___syscall_lstat64, 
___syscall_mkdirat, 
___syscall_newfstatat, 
___syscall_openat, 
___syscall_poll, 
___syscall_readlinkat, 
___syscall_recvfrom, 
___syscall_renameat, 
___syscall_rmdir, 
___syscall_sendto, 
___syscall_socket, 
___syscall_stat64, 
___syscall_symlink, 
___syscall_unlinkat, 
___syscall_utimensat, 
__mmap_js, 
__msync_js, 
__munmap_js, 
_environ_get, 
_environ_sizes_get, 
_fd_close, 
_fd_fdstat_get, 
_fd_pread, 
_fd_pwrite, 
_fd_read, 
_fd_seek, 
_fd_sync, 
_fd_write, 
_getaddrinfo 
];

[pavelsavara]

Also any FS is in UI thread and makes startup slower. We should prevent DLL load to touch FS

[pavelsavara]

_fd_write actually receives buffer with more that one character. That is good enough for now.