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/* This is a test case where the parent process forks 10 children
* which contend to merge profile data to the same file. With
* file locking support, the data from each child should not
* be lost.
*/
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>
void spawn_child(PROCESS_INFORMATION *pi, int child_num) {
wchar_t child_str[10];
_itow(child_num, child_str, 10);
if (!SetEnvironmentVariableW(L"CHILD_NUM", child_str)) {
printf("SetEnvironmentVariableW failed (0x%8lx).\n", GetLastError());
fflush(stdout);
exit(1);
}
STARTUPINFOW si;
memset(&si, 0, sizeof(si));
si.cb = sizeof(si);
memset(pi, 0, sizeof(PROCESS_INFORMATION));
if (!CreateProcessW(NULL, // No module name (use command line)
GetCommandLineW(), // Command line
NULL, // Process handle not inheritable
NULL, // Thread handle not inheritable
TRUE, // Set handle inheritance to TRUE
0, // No flags
NULL, // Use parent's environment block
NULL, // Use parent's starting directory
&si, pi)) {
printf("CreateProcess failed (0x%08lx).\n", GetLastError());
fflush(stdout);
exit(1);
}
}
int wait_child(PROCESS_INFORMATION *pi) {
WaitForSingleObject(pi->hProcess, INFINITE);
DWORD exit_code;
if (!GetExitCodeProcess(pi->hProcess, &exit_code)) {
printf("GetExitCodeProcess failed (0x%08lx).\n", GetLastError());
fflush(stdout);
exit(1);
}
CloseHandle(pi->hProcess);
CloseHandle(pi->hThread);
return exit_code;
}
#define NUM_CHILDREN 10
int foo(int num) {
if (num < (NUM_CHILDREN / 2)) {
return 1;
} else if (num < NUM_CHILDREN) {
return 2;
}
return 3;
}
int main(int argc, char *argv[]) {
char *child_str = getenv("CHILD_NUM");
if (!child_str) {
PROCESS_INFORMATION child[NUM_CHILDREN];
// In parent
for (int i = 0; i < NUM_CHILDREN; i++) {
spawn_child(&child[i], i);
}
for (int i = 0; i < NUM_CHILDREN; i++) {
wait_child(&child[i]);
}
return 0;
} else {
// In child
int child_num = atoi(child_str);
int result = foo(child_num);
if (result == 3) {
fprintf(stderr, "Invalid child count!");
return 1;
}
return 0;
}
}
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