strstr("foobarbarbazbarbop", "foobarbarbazbarbop") = "foobarbarbazbarbop"
strstr("foobarbarbazbarbop", "baz") = "bazbarbop"
strstr("foobarbarbazbarbop", "bar") = "barbarbazbarbop"
strstr("foobarbarbazbarbop", "bazbarbop") = "bazbarbop"
strstr("foobarbarbazbarbop", "barba") = "barbarbazbarbop"
strstr("bazbarbop", "zbarbop") = "zbarbop"
strstr("foobarbarbazbarbop", "") = "foobarbarbazbarbop"
strstr("", "") = ""
strstr("f", "f") = "f"