Fix my breakage. Sorry guys.

[lyx.git] / src / lyx_main.C

diff --git a/src/lyx_main.C b/src/lyx_main.C
index 6dbcca3a226b6e2bf99118023557bcdc936fce6a..3ce8b506d1b14b7356b3fac16476099624fd7454 100644 (file)
--- a/src/lyx_main.C
+++ b/src/lyx_main.C
@@ -280,6 +280,36 @@ void LyX::priv_exec(int & argc, char * argv[])
 }
 
 
+/*
+Signals and Windows
+===================
+The SIGHUP signal does not exist on Windows and does not need to be handled.
+
+Windows handles SIGFPE and SIGSEGV signals as expected.
+
+Cntl+C interrupts (mapped to SIGINT by Windows' POSIX compatability layer)
+cause a new thread to be spawned. This may well result in unexpected
+behaviour by the single-threaded LyX.
+
+SIGTERM signals will come only from another process actually sending
+that signal using 'raise' in Windows' POSIX compatability layer. It will
+not come from the general "terminate process" methods that everyone
+actually uses (and which can't be trapped). Killing an app 'politely' on
+Windows involves first sending a WM_CLOSE message, something that is
+caught already by the Qt frontend.
+
+For more information see:
+
+http://aspn.activestate.com/ASPN/Mail/Message/ActiveTcl/2034055
+...signals are mostly useless on Windows for a variety of reasons that are
+Windows specific...
+
+'UNIX Application Migration Guide, Chapter 9'
+http://msdn.microsoft.com/library/en-us/dnucmg/html/UCMGch09.asp
+
+'How To Terminate an Application "Cleanly" in Win32'
+http://support.microsoft.com/default.aspx?scid=kb;en-us;178893
+*/
 extern "C" {
 
 static void error_handler(int err_sig)
@@ -306,9 +336,11 @@ static void error_handler(int err_sig)
        // This shouldn't matter here, however, as we've already invoked
        // emergencyCleanup.
        switch (err_sig) {
+#ifdef SIGHUP
        case SIGHUP:
                lyxerr << "\nlyx: SIGHUP signal caught\nBye." << endl;
                break;
+#endif
        case SIGFPE:
                lyxerr << "\nlyx: SIGFPE signal caught\nBye." << endl;
                break;
@@ -326,14 +358,20 @@ static void error_handler(int err_sig)
        }
 
        // Deinstall the signal handlers
+#ifdef SIGHUP
        signal(SIGHUP, SIG_DFL);
+#endif
        signal(SIGINT, SIG_DFL);
        signal(SIGFPE, SIG_DFL);
        signal(SIGSEGV, SIG_DFL);
        signal(SIGTERM, SIG_DFL);
 
+#ifdef SIGHUP
        if (err_sig == SIGSEGV ||
            (err_sig != SIGHUP && !GetEnv("LYXDEBUG").empty()))
+#else
+       if (err_sig == SIGSEGV || !GetEnv("LYXDEBUG").empty())
+#endif
                lyx::support::abort();
        exit(0);
 }
@@ -351,7 +389,9 @@ void LyX::printError(ErrorItem const & ei)
 
 void LyX::init(bool gui)
 {
+#ifdef SIGHUP
        signal(SIGHUP, error_handler);
+#endif
        signal(SIGFPE, error_handler);
        signal(SIGSEGV, error_handler);
        signal(SIGINT, error_handler);
@@ -361,8 +401,8 @@ void LyX::init(bool gui)
 #if !defined (USE_POSIX_PACKAGING)
        // Add the directory containing the LyX executable to the path
        // so that LyX can find things like reLyX.
-       if (package.build_support().empty())
-               prependEnvPath("PATH", package.binary_dir());
+       if (package().build_support().empty())
+               prependEnvPath("PATH", package().binary_dir());
 #endif
 
        // Check that user LyX directory is ok. We don't do that if