Thanks, you are correct, I changed the directory structure to:

+---dev
|       hello.c
|       SConstruct.py
|       
\---install-dir

and the SConstruct.py to

env = Environment()
hello = env.Program('hello.c')
env.Install("../install-dir", hello)
env.Alias("install", "../install-dir")

And now the behavior is as described by the docs.

@mwichmann I do have a follow up question actually. I'm now trying with the InstallAs function to change the name of the installed file as follows:

# Change the name of the file upon installation

env = Environment()
hello = env.Program("hello.c")
env.InstallAs("../install-dir/hello-new", hello)
env.Alias("install", "../install-dir")

When I build with scons install it does copy the executable file but doesn't add the .exe extension to it (I'm on Windows). I'm wondering why that is? Isn't SCons supposed to be platform independent? For the time being I've had to change it to the following for the executable to work:

# Change the name of the file upon installation

env = Environment()
hello = env.Program("hello.c")
env.InstallAs("../install-dir/hello-new.exe", hello)
env.Alias("install", "../install-dir")

With InstallAs you're providing the new name to use, the builder takes that very literally. If you want to have it be somewhat independent, you can use the construction variables PROGSUFFIX and SHLIBSUFFIX. Since your destination is a "target" it will have command substitution applied to it (you can't use these everywhere, only in an appropriate context):

env.InstallAs("../install-dir/hello-new$PROGSUFFIX", hello)

See: https://scons.org/doc/production/HTML/scons-man.html#cv-PROGSUFFIX

To see what this is set to:

print("DEBUG: progsuffix is", env['PROGSUFFIX'])