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From: Malcolm McLean <malcolm.arthur.mclean@gmail.com>
Newsgroups: comp.lang.c
Subject: Re: Running an editor from ANSI C
Date: Thu, 6 Jun 2024 09:27:34 +0100
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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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