From 5a1f4b6d37e075cc813a430aa17a97760ae08f72 Mon Sep 17 00:00:00 2001
From: Jeremy <51220084+jeremy-rifkin@users.noreply.github.com>
Date: Thu, 18 Apr 2024 19:38:19 -0500
Subject: [PATCH] Add an error message for exec failures to the signal_demo,
 resolves #111

---
 docs/signal-safe-tracing.md | 3 +++
 test/signal_demo.cpp        | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/docs/signal-safe-tracing.md b/docs/signal-safe-tracing.md
index 681c27e..e51e6d1 100644
--- a/docs/signal-safe-tracing.md
+++ b/docs/signal-safe-tracing.md
@@ -147,6 +147,9 @@ void do_signal_safe_trace(cpptrace::frame_ptr* buffer, std::size_t size) {
         close(input_pipe.read_end);
         close(input_pipe.write_end);
         execl("signal_tracer", "signal_tracer", nullptr);
+        const char* exec_failure_message = "exec(signal_tracer) failed: Make sure the signal_tracer executable is in "
+            "the current working directory and the binary's permissions are correct.\n";
+        write(STDERR_FILENO, exec_failure_message, strlen(exec_failure_message));
         _exit(1);
     }
     // Resolve to safe_object_frames and write those to the pipe
diff --git a/test/signal_demo.cpp b/test/signal_demo.cpp
index 1d7b9a4..1f0d12a 100644
--- a/test/signal_demo.cpp
+++ b/test/signal_demo.cpp
@@ -52,6 +52,9 @@ void handler(int signo, siginfo_t* info, void* context) {
             "signal_tracer",
             nullptr
         );
+        const char* exec_failure_message = "exec(signal_tracer) failed: Make sure the signal_tracer executable is in "
+            "the current working directory and the binary's permissions are correct.\n";
+        write(STDERR_FILENO, exec_failure_message, strlen(exec_failure_message));
         _exit(1);
     }
     for(std::size_t i = 0; i < count; i++) {