--- /dev/null
+--- a/pe_profiling/operf.cpp
++++ b/pe_profiling/operf.cpp
+@@ -857,11 +857,14 @@ static int __delete_old_previous_sample_
+ int tflag __attribute__((unused)),
+ struct FTW *ftwbuf __attribute__((unused)))
+ {
++ int err;
++
+ if (remove(fpath)) {
++ err = errno;
+ perror("sample data removal error");
+- return FTW_STOP;
++ return err;
+ } else {
+- return FTW_CONTINUE;
++ return 0;
+ }
+ }
+
+@@ -896,7 +899,7 @@ static void convert_sample_data(void)
+ return;
+
+ if (!operf_options::append) {
+- int flags = FTW_DEPTH | FTW_ACTIONRETVAL;
++ int flags = FTW_DEPTH;
+ errno = 0;
+ if (nftw(previous_sampledir.c_str(), __delete_old_previous_sample_data, 32, flags) !=0 &&
+ errno != ENOENT) {
+--- a/libop/op_events.c
++++ b/libop/op_events.c
+@@ -83,7 +83,7 @@ static int parse_hex(char const * str)
+ static u64 parse_long_hex(char const * str)
+ {
+ u64 value;
+- if (sscanf(str, "%Lx", &value) != 1)
++ if (sscanf(str, "0x%llx", &value) != 1)
+ parse_error("expected long hexadecimal value");
+
+ fflush(stderr);