Redo the CMake examples; add Ioss example

README.md

@@ -230,15 +230,25 @@ add_executable(ExodusReadFor ExodusRead.f)
 target_link_libraries(ExodusReadFor PRIVATE SEACASExodus_for::all_libs)
 ```
 
-The `cmake-use-example` directory contains this sample
-`CMakeLists.txt` file and a couple C and Fortran files which provide
-an example of how to build and link a C or Fortran program with the
-Exodus library installed as part of a build of this package.
+A similar CMakeLists.txt file for using the IOSS library would be something like:
+
+```sh
+cmake_minimum_required(VERSION 3.1...3.26)
+project(IossCMakeExample VERSION 1.0 LANGUAGES CXX)
+
+#### C++ IOSS ####
+find_package(SEACASIoss CONFIG)
+add_executable(IossExample IossExample.C)
+target_link_libraries(IossExample PRIVATE SEACASIoss::all_libs)
+```
+
+The `cmake-use-example` directory contains Exodus example files in the
+`exodus` subdirectory and Ioss example files in the `ioss` subdirectory.
+These provide short examples of how to build and link a program with the 
+Exodus and/or Ioss libraries.
 
 To use this, copy the contents of the directory to your own filespace
-and modify the contents as needed.  The example provides a C
-executable and a Fortran Executable which both are linked to the
-Exodus library.
+and modify the contents as needed.  
 
 To configure and build, you would do something like:
 
@@ -247,19 +257,10 @@ To configure and build, you would do something like:
   CMAKE_PREFIX_PATH={path_to_root_of_seacas_install} cmake ..
   make
 ```
-And you would then get `ExodusWriteC` and `ExodusReadFor` compiled and linked against the Exodus library.
 
-A similar CMakeLists.txt file for using the IOSS library would be something like:
-
-```sh
-cmake_minimum_required(VERSION 3.1...3.26)
-project(IOSSCMakeExample VERSION 1.0 LANGUAGES CXX)
-
-#### C++ IOSS CMake Example ####
-find_package(SEACASIoss CONFIG)
-add_executable(ioss_exe ioss_exe.C)
-target_link_libraries(ioss_exe PRIVATE SEACASIoss::all_libs)
-```
+And you would then get an executable (`ExodusWriteC` and
+`ExodusReadFor` for Exodus, `IossExample` for Ioss) compiled and linked
+against the Exodus and/or Ioss libraries.
 
 ## Required Software
 

cmake-use-example/CMakeLists.txt → cmake-use-example/exodus/CMakeLists.txt

@@ -16,7 +16,7 @@ add_executable(ExodusWriteC ExodusWrite.c)
 target_link_libraries(ExodusWriteC PRIVATE SEACASExodus::all_libs)
 
 
-#### FORTRAN #####
+#### FORTRAN ##### (Remove all below if only using Exodus C API)
 IF ("${CMAKE_Fortran_COMPILER_ID}" MATCHES "GNU")
   SET(CMAKE_Fortran_FLAGS "${CMAKE_Fortran_FLAGS} -fcray-pointer -fdefault-real-8 -fdefault-integer-8 -fno-range-check")
 ELSEIF ("${CMAKE_Fortran_COMPILER_ID}" MATCHES "XL")

cmake-use-example/ioss/CMakeLists.txt

@@ -0,0 +1,7 @@
+cmake_minimum_required(VERSION 3.1...3.26)
+project(IossCMakeExample VERSION 1.0 LANGUAGES CXX)
+
+#### C++ IOSS ####
+find_package(SEACASIoss CONFIG)
+add_executable(IossExample IossExample.C)
+target_link_libraries(IossExample PRIVATE SEACASIoss::all_libs)

cmake-use-example/ioss/IossExample.C

@@ -0,0 +1,43 @@
+#include <Ionit_Initializer.h>
+#include <Ioss_DatabaseIO.h>
+#include <Ioss_IOFactory.h>
+#include <Ioss_Region.h>
+#include <Ioss_Utils.h>
+
+#include <assert.h>
+#include <iostream>
+#include <string>
+
+int main(int argc, char *argv[]) {
+#ifdef SEACAS_HAVE_MPI
+  MPI_Init(&argc, &argv);
+  ON_BLOCK_EXIT(MPI_Finalize);
+#endif
+
+  if (argc == 1) {
+    std::cerr << "SYNTAX: " << argv[0]
+              << " '--show-config' or 'filename'\n"
+                 "        Will either show the Ioss build configuration\n"
+                 "        Or will show a summary of the data in `filename`\n";
+    std::exit(EXIT_SUCCESS);
+  }
+
+  Ioss::Init::Initializer io;
+  std::string filename = argv[1];
+  if (filename == "--show-config") {
+    std::cerr << Ioss::IOFactory::show_configuration() << "\n";
+  } else {
+    auto dbtype = Ioss::Utils::get_type_from_file(filename);
+    auto *dbi = Ioss::IOFactory::create(dbtype, filename, Ioss::READ_RESTART,
+                                        Ioss::ParallelUtils::comm_world());
+
+    if (dbi == NULL || !dbi->ok(true)) {
+      std::exit(EXIT_FAILURE);
+    }
+
+    // NOTE: 'region' owns 'dbi' pointer at this time and will close
+    // and call dbi destructor.
+    Ioss::Region region(dbi, "example_region");
+    region.output_summary(std::cerr);
+  }
+}