unlink-test.c

#include <stdio.h>
#include <windows.h>

static HANDLE do_open(const char *filename, int access)
{
    return CreateFileA(filename, access, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, OPEN_ALWAYS,
                       FILE_ATTRIBUTE_NORMAL, NULL);
}

static void write_file(const char *filename)
{
    FILE *f = fopen(filename, "w");
    fputs(filename, f);
    fclose(f);
}

int main()
{
    write_file("locked-read");
    HANDLE f1 = do_open("locked-read", GENERIC_READ);
    printf("unlink: %d\n", unlink("locked-read"));
    HANDLE f2 = do_open("locked-read", GENERIC_WRITE);
    if (f2 == INVALID_HANDLE_VALUE)
        printf("create failed\n");
    else
        CloseHandle(f2);
    CloseHandle(f1);
    return 0;
}