Re: Running an editor from ANSI C

On 2024-06-07, Malcolm McLean <malcolm.arthur.mclean@gmail.com> wrote:

On 07/06/2024 21:04, Scott Lurndal wrote:

How does your pure "C" shell
spawn a new process without using posix or other OS-specific
APIs?

>
It can call "system".

1. System is an interface to someone else's existing shell1

2. To do process coordination using "system", you will have to
   rely on implementation-specific syntax, like POSIX.
   For instance system("command1 | command2 > file").
   As soon as you rely on any specific command syntax in
   system(), your program is no longer maximally portable ISO C;
   it is a mixed-language program.

3. A conforming C implementation need not provide a command
   interpreter, in which case system(NULL) returns zero.

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