Ignore SIGPIPE at startup to prevent crashes on dropped printer connections (#13788)

Ignore SIGPIPE at startup to prevent crash on dropped printer connection

Writing to a closed printer network socket raised SIGPIPE, whose default
action terminated the whole process (exit 141, no crash report). Set
SIGPIPE to SIG_IGN once at main() entry (POSIX only) so such writes return
EPIPE to the existing networking error handling instead of killing the app.

Fixes #13787

src/OrcaSlicer.cpp

@@ -23,6 +23,7 @@
 #include <cstring>
 #include <iostream>
 #include <math.h>
+#include <csignal>
 
 #if defined(__linux__) || defined(__LINUX__)
 #include <condition_variable>
@@ -7459,6 +7460,13 @@ extern "C" {
 #else /* _MSC_VER */
 int main(int argc, char **argv)
 {
+#ifndef _WIN32
+    // Ignore SIGPIPE so a write to a closed socket (e.g. a dropped printer
+    // network connection) returns EPIPE to the caller instead of terminating
+    // the whole process. Without this, losing the printer link kills
+    // OrcaSlicer with SIGPIPE (exit 141) and produces no crash report.
+    std::signal(SIGPIPE, SIG_IGN);
+#endif
     return CLI().run(argc, argv);
 }
 #endif /* _MSC_VER */