What is a good way to do general execs?

[Guy Harris]

 >|The Bourne shell sources ".profile" *only* for login shells (just as the
 >|C shell sources ".login" only for login shells - the "-f" in
 >|"#! /bin/csh -bf" is there to prevent it from sourcing your ".cshrc").
 >
 >Nope. For the man page for 'sh': 
 > 
 >     Invocation. 
 >     If the first character of argument zero is -, commands are 
 >     read from $HOME/.profile, if such a file exists.   

I consider "login shell" basically short for "shell with the first
character of argument zero a '-'" (which means that any shell fired up
by "login" is a login shell, but so are shells fired up by e.g.  "su"
when run with the appropriate flag).  I considered the more detailed
explanation unnecessary and extraneous in this case....