
Help("""

  This is the first scons example. In this example we see a very simple way
  of calling scons to create an executable
  
>> ls
main.cpp  SConstruct

>> scons -h (get this help message)
>> scons -H (get scons command help)
usage: scons [OPTION] [TARGET] ...

SCons Options:
  -b, -d, -e, -m, -S, -t, -w, --environment-overrides, --no-keep-going,
  --no-print-directory, --print-directory, --stop, --touch
                              Ignored for compatibility.
  -c, --clean, --remove       Remove specified targets and dependencies.
  -C DIR, --directory=DIR     Change to DIR before doing anything.
  --cache-debug=FILE          Print CacheDir debug info to FILE.
  --cache-disable, --no-cache
                              Do not retrieve built targets from CacheDir.
  --cache-force, --cache-populate
                              Copy already-built targets into the CacheDir.
  --cache-readonly            Do not update CacheDir with built targets.
  --cache-show                Print build actions for files from CacheDir.
  --config=MODE               Controls Configure subsystem: auto, force,
                                cache.
  -D                          Search up directory tree for SConstruct,
                                build all Default() targets.
  --debug=TYPE                Print various types of debugging information:
                                count, duplicate, explain, findlibs, includes,
                                memoizer, memory, objects, pdb, prepare,
                                presub, stacktrace, time.
  --diskcheck=TYPE            Enable specific on-disk checks.
  --duplicate=DUPLICATE       Set the preferred duplication methods. Must be
                                one of hard-soft-copy, soft-hard-copy,
                                hard-copy, soft-copy, copy
  -f FILE, --file=FILE, --makefile=FILE, --sconstruct=FILE
                              Read FILE as the top-level SConstruct file.
  -h, --help                  Print defined help message, or this one.
  -H, --help-options          Print this message and exit.
  -i, --ignore-errors         Ignore errors from build actions.
  -I DIR, --include-dir=DIR   Search DIR for imported Python modules.
  --implicit-cache            Cache implicit dependencies
  --implicit-deps-changed     Ignore cached implicit dependencies.
  --implicit-deps-unchanged   Ignore changes in implicit dependencies.
  --interact, --interactive   Run in interactive mode.
  -j N, --jobs=N              Allow N jobs at once.
  -k, --keep-going            Keep going when a target can't be made.
  --max-drift=N               Set maximum system clock drift to N seconds.
  --md5-chunksize=N           Set chunk-size for MD5 signature computation to
                                N kilobytes.
  -n, --no-exec, --just-print, --dry-run, --recon
                              Don't build; just print commands.
  --no-site-dir               Don't search or use the usual site_scons dir.
  --profile=FILE              Profile SCons and put results in FILE.
  -q, --question              Don't build; exit status says if up to date.
  -Q                          Suppress "Reading/Building" progress messages.
  --random                    Build dependencies in random order.
  -s, --silent, --quiet       Don't print commands.
  --site-dir=DIR              Use DIR instead of the usual site_scons dir.
  --stack-size=N              Set the stack size of the threads used to run
                                jobs to N kilobytes.
  --taskmastertrace=FILE      Trace Node evaluation to FILE.
  --tree=OPTIONS              Print a dependency tree in various formats: all,
                                derived, prune, status.
  -u, --up, --search-up       Search up directory tree for SConstruct,
                                build targets at or below current directory.
  -U                          Search up directory tree for SConstruct,
                                build Default() targets from local SConscript.
  -v, --version               Print the SCons version number and exit.
  --warn=WARNING-SPEC, --warning=WARNING-SPEC
                              Enable or disable warnings.
  -Y REPOSITORY, --repository=REPOSITORY, --srcdir=REPOSITORY
                              Search REPOSITORY for source and target files.

>> scons
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Building targets ...
g++ -o main.o -c main.cpp
g++ -o helloworld main.o
scons: done building targets.


>> scons
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Building targets ...
scons: `.' is up to date.
scons: done building targets.


>> ls -a
total 32
drwxr-xr-x 2 brgirgis users    96 Sep 26 22:50 ./
drwxr-xr-x 5 brgirgis users    36 Sep 26 22:44 ../
-rwxr-xr-x 1 brgirgis users 13176 Sep 26 22:50 helloworld*
-rw-r--r-- 1 brgirgis users    94 Sep 26 22:20 main.cpp
-rw-r--r-- 1 brgirgis users  2728 Sep 26 22:50 main.o
-rw-r--r-- 1 brgirgis users  1749 Sep 26 22:50 .sconsign.dblite
-rw-r--r-- 1 brgirgis users   400 Sep 26 22:50 SConstruct

>> scons -c
scons: Reading SConscript files ...
scons: done reading SConscript files.
scons: Cleaning targets ...
Removed main.o
Removed helloworld
scons: done cleaning targets.


>> ls -a
total 12
drwxr-xr-x 2 brgirgis users   64 Sep 26 22:53 ./
drwxr-xr-x 5 brgirgis users   36 Sep 26 22:44 ../
-rw-r--r-- 1 brgirgis users   94 Sep 26 22:20 main.cpp
-rw-r--r-- 1 brgirgis users 1759 Sep 26 22:51 .sconsign.dblite
-rw-r--r-- 1 brgirgis users 1178 Sep 26 22:54 SConstruct

""")

Program('helloworld', 'main.cpp')
