Hi, I believe this is a very useful tool when you only want to execute simple CPP tests! Here are two errors I encountered while trying to use it:

1. There are a few errors when the CPP file is not in the current directory:

$ cat ./some/path/to/file/main.cpp

!/usr/bin/env cppsh

include

int main()
{
std::cout << "Execution OK." << std::endl;
}

$ cppsh ./some/path/to/file/main.cpp
/usr/local/bin/cppsh: line 35: /tmp/./some/path/to/file/main.cpp: No such file or directory
/usr/local/bin/cppsh: line 36: /tmp/./some/path/to/file/main.cpp: No such file or directory
g++: error: /tmp/./some/path/to/file/main.cpp: No such file or directory
g++: fatal error: no input files
compilation terminated.

$ cd ./some/path/to/file
$ cppsh main.cpp
Execution OK.

1. You can also see errors when your CPP file doesn't use the shebang,
   (a check for #! could be added before removing the first line)

$ cat main_without_shebang.cpp

include

int main()
{
std::cout << "Execution OK." << std::endl;
}

$ cppsh main_without_shebang.cpp
/tmp/main_without_shebang.cpp: In function ‘int main()’:
/tmp/main_without_shebang.cpp:5:2: error: ‘cout’ is not a member of ‘std’
/tmp/main_without_shebang.cpp:5:34: error: ‘endl’ is not a member of ‘std’

$ cat /tmp/main_without_shebang.cpp
// auto-generated

int main()
{
std::cout << "Execution OK." << std::endl;
}