Added patch for interrupt handling if we want to add it at some point.

signal.patch

@@ -0,0 +1,148 @@
+diff --git a/.gitignore b/.gitignore
+index 99ecbed..6e86cf7 100644
+--- a/.gitignore
++++ b/.gitignore
+@@ -3,6 +3,7 @@
+ *.mod
+ *.log
+ *.out
++*__genmod.f90
+ 
+ # Compiler python objects
+ *.pyc
+diff --git a/src/Makefile b/src/Makefile
+index a5c9237..d6c1bba 100644
+--- a/src/Makefile
++++ b/src/Makefile
+@@ -33,6 +33,7 @@ GIT_SHA1 = $(shell git log -1 | head -n 1 | awk '{print $$2}')
+ #===============================================================================
+ 
+ ifeq ($(COMPILER),gnu)
++  CC = gcc
+   F90 = gfortran
+   F90FLAGS := -cpp -fbacktrace -DNO_F2008
+   LDFLAGS =
+@@ -61,6 +62,7 @@ endif
+ #===============================================================================
+ 
+ ifeq ($(COMPILER),intel)
++  CC = icc
+   F90 = ifort
+   F90FLAGS := -cpp -warn -assume byterecl -traceback
+   LDFLAGS =
+@@ -88,6 +90,7 @@ endif
+ #===============================================================================
+ 
+ ifeq ($(COMPILER),pgi)
++  CC = pgcc
+   F90 = pgf90
+   F90FLAGS := -Mpreprocess -DNO_F2008 -Minform=inform -traceback
+   LDFLAGS =
+@@ -115,6 +118,7 @@ endif
+ #===============================================================================
+ 
+ ifeq ($(COMPILER),ibm)
++  CC = xlc
+   F90 = xlf2003
+   F90FLAGS := -WF,-DNO_F2008 -O2
+ 
+@@ -206,7 +210,7 @@ distclean: clean
+ 	cd xml-fortran; make clean
+ 	cd xml-fortran/templates; make clean
+ clean:
+-	@rm -f *.o *.mod $(program)
++	@rm -f *.o *.mod *__genmod.f90 $(program)
+ neat:
+ 	@rm -f *.o *.mod
+ 
+@@ -220,6 +224,9 @@ neat:
+ %.o: %.F90
+ 	$(F90) $(F90FLAGS) -DGIT_SHA1="\"$(GIT_SHA1)\"" -Ixml-fortran -Ixml-fortran/templates -c $<
+ 
++csignal.o: csignal.c
++	$(CC) -c $<
++
+ #===============================================================================
+ # Dependencies
+ #===============================================================================
+diff --git a/src/OBJECTS b/src/OBJECTS
+index 0daf0f1..a476eb6 100644
+--- a/src/OBJECTS
++++ b/src/OBJECTS
+@@ -4,6 +4,7 @@ ace_header.o \
+ bank_header.o \
+ cross_section.o \
+ criticality.o \
++csignal.o \
+ datatypes.o \
+ datatypes_header.o \
+ doppler.o \
+@@ -17,6 +18,7 @@ fixed_source.o \
+ geometry.o \
+ geometry_header.o \
+ global.o \
++handle_sigint.o \
+ hdf5_interface.o \
+ initialize.o \
+ intercycle.o \
+diff --git a/src/csignal.c b/src/csignal.c
+new file mode 100644
+index 0000000..96bfdb5
+--- /dev/null
++++ b/src/csignal.c
+@@ -0,0 +1,7 @@
++#include <signal.h>
++
++typedef void (*sighandler_t)(int);
++void signal_(int* signum, sighandler_t handler)
++{
++  signal(*signum, handler);
++}
+diff --git a/src/handle_sigint.F90 b/src/handle_sigint.F90
+new file mode 100644
+index 0000000..b2f7d1b
+--- /dev/null
++++ b/src/handle_sigint.F90
+@@ -0,0 +1,27 @@
++!===============================================================================
++! HANDLE_SIGINT
++!===============================================================================
++
++subroutine handle_sigint()
++
++  use, intrinsic :: ISO_FORTRAN_ENV
++
++  integer :: option ! selected user option
++
++  ! Display interrupt options
++  write(OUTPUT_UNIT,*)  'Run interrupted. Select one of the options below:'
++  write(OUTPUT_UNIT,*)  '  1. Continue simulation'
++  write(OUTPUT_UNIT,*)  '  2. Kill simulation'
++
++  ! Read input from user
++  read(INPUT_UNIT,*) option
++
++  ! Handle selected option
++  select case (option)
++  case (1)
++     return
++  case (2)
++     stop
++  end select
++
++end subroutine handle_sigint
+diff --git a/src/initialize.F90 b/src/initialize.F90
+index 60c0806..8cac6a5 100644
+--- a/src/initialize.F90
++++ b/src/initialize.F90
+@@ -46,6 +46,10 @@ contains
+ 
+   subroutine initialize_run()
+ 
++    ! Set up signal handler for SIGINT
++    external handle_sigint
++    call signal(2, handle_sigint)
++
+     ! Start total and initialization timer
+     call timer_start(time_total)
+     call timer_start(time_initialize)