Re: Running an editor from ANSI C

On 06/06/2024 05:40, Janis Papanagnou wrote:

On 06.06.2024 04:47, Malcolm McLean wrote:

>

The concept is an ANSI C only shell.
>
I can write my own text editor on top of Posix easily enough.
But I want to implent an "edit" command so that users can edit files.
>
And you just can't edit files without non-ASCII keys.

 What do you mean here? You certainly can edit files with Vi-like
ASCII-key commands (as, for example, some shells do to allow edit
their history file).
 

So at the moment I call system with nano, and it wotks. But it's a
clunky solution.

 Nano at least relies on some control-keys. (Is that no issue?)
 There's a couple of professional systems that allow to spawn any
editor (that fits basic calling conventions) that suits you, which
is a Good Thing. It's IMO generally a good approach to not force
folks to use some specific (or even proprietary) editor in context
of an application. (Not that this design practice would be widely
observable in practice.)
 Janis
 

This is the current code for the "edit" command.
  else if (!strcmp(command, "edit"))
    {
        char *exportargs[4];
        char *importargs[4];
        char buff[1024];
        if (argc == 2)
        {
            char *tempfile = 0;
            tempfile = tmpnam(0);
            if (tempfile)
            {
                exportargs[0] = "export";
                exportargs[1] = argv[1];
                exportargs[2] = tempfile;
                exportargs[3] = 0;
                export(shell, 3, exportargs);
                snprintf(buff, 1024, "%s %s\n", shell->editor, tempfile);
                system(buff);
                importargs[0] = "import";
                importargs[1] = tempfile;
                importargs[2] = argv[1];
                importargs[3] = 0;
                import(shell, 3, importargs);
            }
        }
    }
It does work. But my compiler warns about rmpnam() being deprecated.
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