Tested and corrected program listing from GETTING_STARTE.md.

Author: Damian Rouson

GETTING_STARTED.md

@@ -27,61 +27,65 @@ grow over time.  Please submit bug reports and feature requests via our [Issues]
 The "caf" script liberates the source code and workflow from explicit dependence on the
 underlying compiler and communication library in the following ways: 
 
-1. "caf" automatically embeds the relevant library path (e.g., libcaf_mpi.a) in the compile command.
-2.  With a non-CAF compiler (including gfortran 4.9), "caf" supports a subset of CAF by replacing 
-    CAF statements with calls to procedures in the [opencoarrays] module.  
-3.  With non-CAF compilers and non-gfortran CAF compilers, "caf" includes in the compile statement
-    the .mod file that the CMake scripts install in the "mod" suddierctory of the installation path.  
-    This enables uers to access OpenCoarrays capabilities via use association (i.e.  "use opencoarrays"). 
-    To avoid inadvertent procedure name overloading with non-gfortra CAF compilers, we recommend using 
-    statements of the form "use opencoarrays, only : co_reduce" to reduce the number name classes.
-4.  With a non-gfortran CAF compiler (e.g., Cray and Intel), "caf" extends the compiler's capabilities 
-    by providing features that are proposed for Fortran 2015 in the draft Technical Specification 
-    [TS18508 Additional Parallel Features in Fortran].
+1. With an OpenCoarrays-aware (OCA) CAF compiler, the "caf" script passes the unmodified
+   source code to the underlying compiler with the necessary arguments for building a 
+   CAF program, embedding the paths to OpenCoarrays libraries (e.g., libcaf_mpi.a) installed 
+   in the "lib" subdirectory of the OpenCoarrays installation path.  The "caf" script also 
+   embeds the path to the relevant module file in the "mod" subdirectory of the installation
+   path (e.g., opencoarrays.mod).  This supports use association with module entities via
+   ``use opencoarrays``.
+2. With a non-CAF compiler (including gfortran 4.9), "caf" supports a subset of CAF by 
+   replacing CAF statements with calls to procedures in the [opencoarrays module] before
+   passing the source code to the compiler.  
+
+When using GCC 4.9, we recommend using the `use` statement's "only" clause to
+avoid inadvertent procedure name clashes between OpenCoarrays procedures and their 
+GCC counerparts.  For example, use "use opencoarrays, only : co_reduce".
+
+With a non-OCA and OCA CAF compilers, the extensions that "caf" imports include the collective
+subroutines proposed for Fortran 2015 in the draft Technical Specification [TS 18508]
+_Additional Parallel Features in Fortran_.
 
 The latter use case provides an opportunity to mix a compiler's CAF support with that of OpenCoarrays.  
-For example, a non-gfortran CAF compiler might support all of a program's coarray square-bracket syntax, 
-while OpenCoarrays supports the same program's calls to collective subrouine such as co_sum and co_reduce.
+For example, a non-OCA CAF compiler, such as the Cray or Intel compilers, might support all of a 
+program's coarray square-bracket syntax, while OpenCoarrays supports the same program's calls to 
+collective subroutine such as `co_sum` and `co_reduce`.
 
 <a name="a-sample-basic-workflow">
 ### A sample basic workflow ###
 </a>
 
+## Compiling and Running with an OpenCoarrays-aware (OCA) CAF Compiler</a> ##
+
 Inserting the "bin" directory of the chosen installation path into the user's PATH enables the following
 CAF program compilation and execution workflow:
 
-    $ cat sum_image_numbers.f90
-    program main
-      use iso_c_binding, only : c_int
-      use iso_fortran_env, only : error_unit
-      implicit none
-      integer(c_int) :: tally
-      tally = this_image() ! this image's contribution 
-      call co_sum(tally)
-      verify: block
-        integer(c_int) :: image
-        if (tally/=[(image,image=1,num_images())]) then
-           write(error_unit,'(a,i5)') "Incorrect tally on image ",this_image()
-           error stop
-        end if
-      end block verify
-      ! Wait for all images to pass the test
-      sync all
-      if (this_image()==1) print *,"Test passed"
-    end program
-    
- ```   
-    $ caf sum_image_numbers.f90
-    $ caf sum_image_numbers.f90
-    $ cafrun -np 4 ./sum_image_numbers
-      Test passed.
-```      
-where "4" is the number of images to be launched at program start-up.
+      $ cat tally.f90 
+      program main
+        use iso_c_binding, only : c_int
+        use iso_fortran_env, only : error_unit
+        implicit none
+        integer(c_int) :: tally
+        tally = this_image() ! this image's contribution 
+        call co_sum(tally)
+        verify: block
+          integer(c_int) :: image
+          if (tally/=sum([(image,image=1,num_images())])) then
+             write(error_unit,'(a,i5)') "Incorrect tally on image ",this_image()
+             error stop
+          end if
+        end block verify
+        ! Wait for all images to pass the test
+        sync all 
+        if (this_image()==1) print *,"Test passed"
+      end program
+      $ caf tally.f90 -o tally
+      $ cafrun -np 4 ./tally
+        Test passed
 
-<a name="sample-advanced-workflow">
-### Sample advanced workflows</a> ###
+where "4" is the number of images to be launched at program start-up.
 
-<a name="Extending a non-OCA CAF COmpiler
+<a name="extending-a-non-oca-CAF-compiler"
 ## Extending a Non-OCA CAF Compiler</a> ##
 
 To extend the capabilities of a non-OCA CAF compiler (e.g., the Intel or Cray compilers) 
@@ -93,24 +97,23 @@ in the above example:
 
 Then compile with the "caf" compiler wrapper and launch with "cafrun" program launcher.
 
-<a name="compiling-without-caf">
-## Sample Advanced Workflow</a> ##
+<a name="sample-advanced-workflow">
+### A sample advanced workflows</a> ###
 
 If the "caf" compiler wrapper cannot process the source code in question, invoke
 the underlying communication library directly:
 
-    mpif90 -fcoarray=lib -L/opt/opencoarrays/ hello.f90 \ -lcaf_mpi -o hello -I<OpenCoarrays-install-path>/mod
+    mpif90 -fcoarray=lib -L/opt/opencoarrays/ tally.f90 \ -lcaf_mpi -o htally-I<OpenCoarrays-install-path>/mod
 
 and also run the program with the lower-level commnication library:
 
-    mpirun -np <number-of-images> ./hello
-
+    mpirun -np <number-of-images> ./tally
 
 
 [Sourcery Store]: http://www.sourceryinstitute.org/store
 [Virtualbox]: http://www.virtualbox.org
 [Issues]: https://github.com/sourceryinstitute/opencoarrays/issues
-[opencoarrays]: ./src/extensions/opencoarrays.F90
+[opencoarrays module]: ./src/extensions/opencoarrays.F90
 [GCC]: http://gcc.gnu.org
 [TS18508 Additional Parallel Features in Fortran]: http://isotc.iso.org/livelink/livelink?func=ll&objId=17181227&objAction=Open
 [The caf compiler wrapper]: #the-caf-compiler-wrapper