test/pthread/test_pthread_file_io.c

// Copyright 2015 The Emscripten Authors.  All rights reserved.
// Emscripten is available under two separate licenses, the MIT license and the
// University of Illinois/NCSA Open Source License.  Both these licenses can be
// found in the LICENSE file.

#include <pthread.h>
#include <emscripten/console.h>
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static void *thread1_start(void *arg) {
  emscripten_out("thread1_start!");

  FILE *handle = fopen("file1.txt", "r");
  assert(handle);
  char str[256] = {};
  fgets(str, 255, handle);
  fclose(handle);
  assert(!strcmp(str, "hello!"));

  handle = fopen("file2.txt", "w");
  fputs("hello2!", handle);
  fclose(handle);

  pthread_exit(0);
}

int main() {
  FILE *handle = fopen("file1.txt", "w");
  fputs("hello!", handle);
  fclose(handle);
  pthread_t thr;
  pthread_create(&thr, NULL, thread1_start, 0);
  pthread_join(thr, 0);

  handle = fopen("file2.txt", "r");
  char str[256] = {};
  fgets(str, 255, handle);
  fclose(handle);
  assert(!strcmp(str, "hello2!"));

  return 0;
}