Path: utzoo!attcan!uunet!mcvax!ukc!warwick!geoff
From: geoff@cs.warwick.ac.uk (Geoff Rimmer)
Newsgroups: comp.lang.c
Subject: Re: execl()'ing batch files in DOS
Message-ID: <1914@ubu.warwick.UUCP>
Date: 23 May 89 17:31:44 GMT
References: <302@ohs.UUCP>
Sender: news@warwick.UUCP
Organization: Computer Science, Warwick University, UK
Lines: 51
In-reply-to: mday@ohs.UUCP's message of 16 May 89 19:34:02 GMT


In article <302@ohs.UUCP> mday@ohs.UUCP (Matthew T. Day) writes:
> Does anybody know if it's possible to execl() a batch file in DOS?  I am
> using MicroSoft C v5.1, and using MS-DOS v3.30.  I have tried:
> 
> 	execl("\command.com", "tryit.bat", NULL);
> 
> and perror() tells me "No such file or directory."  Any help or input would
> be appreciated.

The \ character when in a string constant has a special meaning.  In
particular, it is used to produce special characters sucg as \n \t \r
\a \v etc.  To get a real \, you should double it: "\\command.com".
What you have written is actually undefined (according to ANSI C anyway).

BTW in QuickC (and also MSC5.1), you are often allowed to use the
UNIX-style '/' when calloing library functions such as "fopen".  Note
however that this will not work with the "system" function, and
probably not with the exec and spawn family of functions.

I was under the impression that to execute a batch file, you should
do:

	command.com -c batch.bat

In which case, you would require the following:

	execl("\\command.com", "\\command.com", "-c", "batch.bat", (char *)0);
		[a]		[b]		[c]	[d]		[e]

[a] says where the program is to be found.
[b] is argv[0] when command.com is run.
[c] is the command flag.
[d] is the batch file to run.
[e] is a pointer to char NULL.

Or maybe there's something about command.com that I don't know about?

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	|	GEOFF RIMMER						|
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