Open or attach to a console when executing system commands

ChangeLog

@@ -1,3 +1,12 @@
+2017-10-01  Bastian Maerkisch  <[email protected]>
+
+	* src/win/winmain.c|h src/command.c:  For wgnuplot, open or attach to a
+	console when executing system commands so we can its the output.  That
+	in my option eliminates the last benefit of wgnuplot_pipes over
+	wgnuplot.  Note that the process terminates if the new console is
+	closed, just as is the case with wgnuplot_pipes, but the console is
+	only opened when actually required.
+
 2017-09-29  Ethan A Merritt  <[email protected]>
 
 	* src/axis.h src/axis.c (axis_set_scale_and_range):  Incorrect use

src/command.c

@@ -1,5 +1,5 @@
 #ifndef lint
-static char *RCSid() { return RCSid("$Id: command.c,v 1.363 2017-09-29 19:38:02 sfeam Exp $"); }
+static char *RCSid() { return RCSid("$Id: command.c,v 1.364 2017-10-01 09:01:57 markisch Exp $"); }
 #endif
 
 /* GNUPLOT - command.c */
@@ -124,12 +124,12 @@ int thread_rl_RetCode = -1; /* return code from readline in a thread */
 #ifdef _WIN32
 # define WIN32_LEAN_AND_MEAN
 # include <windows.h>
-# ifdef __MSC__
+# ifdef _MSC_VER
 #  include <malloc.h>
 #  include <direct.h>          /* getcwd() */
 # else
 #  include <alloc.h>
-# endif				/* !MSC */
+# endif
 # include <htmlhelp.h>
 # include "win/winmain.h"
 #endif /* _WIN32 */
@@ -3090,6 +3090,10 @@ do_system(const char *cmd)
     if (!cmd)
 	return;
     restrict_popen();
+#if defined(_WIN32) && !defined(WGP_CONSOLE)
+    /* Open a console so we can see the command's output */
+    WinOpenConsole();
+#endif
 #if defined(_WIN32) && !defined(__WATCOMC__)
     {
 	LPWSTR wcmd = UnicodeText(cmd, encoding);

src/win/winmain.c

@@ -1,5 +1,5 @@
 /*
- * $Id: winmain.c,v 1.104 2017-09-01 05:21:01 markisch Exp $
+ * $Id: winmain.c,v 1.105 2017-10-01 09:01:57 markisch Exp $
  */
 
 /* GNUPLOT - win/winmain.c */
@@ -1082,6 +1082,7 @@ fake_pclose(FILE *stream)
 }
 #endif
 
+
 #ifdef WGP_CONSOLE
 
 DWORD WINAPI
@@ -1465,6 +1466,22 @@ WinMessageLoop(void)
 }
 
 
+#ifndef WGP_CONSOLE
+void
+WinOpenConsole(void)
+{
+    /* Try to attach to an existing console window. */
+    if (AttachConsole(ATTACH_PARENT_PROCESS) == 0) {
+	if (GetLastError() != ERROR_ACCESS_DENIED) {
+	    /* Open new console if we are are not attached to one already.
+	       Note that closing this console window will end wgnuplot, too. */
+	    AllocConsole();
+	}
+    }
+}
+#endif
+
+
 void
 WinRaiseConsole(void)
 {

src/win/winmain.h

@@ -1,5 +1,5 @@
 /*
- * $Id: winmain.h,v 1.20 2016-08-06 13:22:50 markisch Exp $
+ * $Id: winmain.h,v 1.21 2017-10-01 09:01:57 markisch Exp $
  */
 
 /* GNUPLOT - win/winmain.h */
@@ -71,6 +71,7 @@ void win_sleep(DWORD dwMilliSeconds);
 TBOOLEAN WinAnyWindowOpen(void);
 void WinPersistTextClose(void);
 void WinMessageLoop(void);
+void WinOpenConsole(void);
 void WinRaiseConsole(void);
 UINT WinGetCodepage(enum set_encoding_id encoding);
 enum set_encoding_id WinGetEncoding(UINT cp);