From abe6c4db686bf67e35eb393a83794342e1051273 Mon Sep 17 00:00:00 2001
From: Markus Pfeiffer <markus.pfeiffer@st-andrews.ac.uk>
Date: Tue, 21 Aug 2018 15:41:58 +0100
Subject: [PATCH 1/2] Introduce command line options --norepl and --nointeract
 to disable GAP shell

* --norepl just disables the read-evaluate-print-loop, so GAP can still
  go into a break loop

* --nointeract disables both the repl and the break loop
---
 lib/system.g | 13 ++++++++++++-
 1 file changed, 12 insertions(+), 1 deletion(-)

diff --git a/lib/system.g b/lib/system.g
index 7961f01746..df24746af2 100644
--- a/lib/system.g
+++ b/lib/system.g
@@ -111,7 +111,11 @@ BIND_GLOBAL( "GAPInfo", rec(
            help := [ "Run ProfileLineByLine(<filename>) with recordMem := true on GAP start"] ),
       rec( long := "cover", default := "", arg := "<file>",
            help := [ "Run CoverageLineByLine(<filename>) on GAP start"] ),
-      rec( long := "enableMemCheck", default := false)
+      rec( long := "enableMemCheck", default := false),
+      rec( long := "norepl", default := false,
+           help := [ "Disable the GAP read-evaluate-print loop (REPL)" ] ),
+      rec( long := "nointeract", default := false,
+           help := [ "Start GAP in non-interactive mode (disable read-evaluate-print loop (REPL) and break loop)" ] )
     ],
     ) );
 
@@ -377,6 +381,13 @@ CallAndInstallPostRestore( function()
     CommandLineOptions.g:= CommandLineOptions.g mod 3;
     # use the same as the kernel
     CommandLineOptions.E:= GAPInfo.KernelInfo.HAVE_LIBREADLINE;
+
+    # --nointeract implies no break loop and no repl
+    if CommandLineOptions.nointeract then
+      CommandLineOptions.T := true;
+      CommandLineOptions.norepl := true;
+    fi;
+
     MakeImmutable( CommandLineOptions );
     MakeImmutable( InitFiles );
 

From 5857c9720d09d082b5c90ccb6d6c258d06c0d836 Mon Sep 17 00:00:00 2001
From: Markus Pfeiffer <markus.pfeiffer@st-andrews.ac.uk>
Date: Tue, 21 Aug 2018 15:42:33 +0100
Subject: [PATCH 2/2] Remove IsLIBGAP constant

The presence of the `--norepl` command line option makes the `IsLIBGAP`
constant obsolete, so we remove it.
---
 lib/init.g                   | 15 +++------------
 tst/testinstall/IsLIBGAP.tst | 11 -----------
 2 files changed, 3 insertions(+), 23 deletions(-)
 delete mode 100644 tst/testinstall/IsLIBGAP.tst

diff --git a/lib/init.g b/lib/init.g
index bb5f570b20..ecbb1ed552 100644
--- a/lib/init.g
+++ b/lib/init.g
@@ -938,16 +938,6 @@ BindGlobal ("ShowSystemInformation", function ()
 end );
 
 
-#############################################################################
-##
-## Initialize the IsLIBGAP variable (if not done before). If this variable
-## is false, an interactive session will be started.
-## Otherwise no interactive session is started.
-##
-if not IsBound( IsLIBGAP ) then
-  BIND_CONSTANT( "IsLIBGAP", false );
-fi;
-
 #############################################################################
 ##
 ##  Finally, deal with the lists of global variables.
@@ -1037,8 +1027,9 @@ InstallAndCallPostRestore( function()
     od;
 end );
 
-if IsLIBGAP then
-  # GAP is used as a library, do not start an interactive session
+
+if GAPInfo.CommandLineOptions.norepl then
+  # do not start an interactive session
 elif IsHPCGAP and THREAD_UI() then
   ReadLib("hpc/consoleui.g");
   MULTI_SESSION();
diff --git a/tst/testinstall/IsLIBGAP.tst b/tst/testinstall/IsLIBGAP.tst
deleted file mode 100644
index a728214a11..0000000000
--- a/tst/testinstall/IsLIBGAP.tst
+++ /dev/null
@@ -1,11 +0,0 @@
-#############################################################################
-##
-#W  IsLIBGAP.tst                  GAP library               Sebastian Gutsche
-##
-##
-#Y  Copyright (C)  2018,  GAP Group
-##
-gap> START_TEST("IsLIBGAP.tst");
-gap> IsBound( IsLIBGAP );
-true
-gap> STOP_TEST( "IsLIBGAP.tst", 1);