Major Mode Determination from File Contents

Major Mode Determination from File Contents

[Adalbert Perbandt]

Hi there,

I have a serious problem with automatically setting a specific mode
for files depending on their contents. 

Due to some good reason we had to insert this header into our Perl
script files:

#!/bin/sh
exec $IW_PERL -x -w -S $0 ${1+"$@"}

Now I no longer could place -*- cperl -*- into the first line because
this would confuse the execve system call which executes some of these
files.

Until now I know these ways to specify the mode for a file
automagically:

1. By extension -- Doesn't fit here because the perl scripts do not
have any extension.

2. By placing the above given line in the first nonempty line of the
file -- No longer possible.

3. Local Variable list at the end of the file -- Would work but looks
somewhat ugly.

4. Setup of interpreter-mode-alist Variable -- Doesn't work because
only the first line is processed by this mechanism.

Is their any other way to put the "-*- cperl -*-" line near the top of
the file and get it processed by some mode determination mechanism? 

Any ideas would be welcome.

Thanks,

Adalbert Perbandt.

Re: Major Mode Determination from File Contents

[Glenn Morris]

Adalbert Perbandt wrote:

[can't set file local variables in shell scripts]

Emacs info node "Local Variables in Files":

    In shell scripts, the first line is used to identify the script
    interpreter, so you cannot put any local variables there. To
    accommodate for this, when Emacs visits a shell script, it looks
    for local variable specifications in the _second_ line.

Re: Major Mode Determination from File Contents

[Adalbert Perbandt]

Glenn Morris <gmorris+news@ast.cam.ac.uk> writes:

> Adalbert Perbandt wrote:

[...] 
> Emacs info node "Local Variables in Files":
[...]

Thanks a lot! Works fine. Unfortunately the text you quoted was not
contained in the info doc for XEmacs 21.4.12 which I use.

Regards,

Adalbert Perbandt. 

Re: Major Mode Determination from File Contents

[Glenn Morris]

Adalbert Perbandt wrote:

> Unfortunately the text you quoted was not contained in the info doc
> for XEmacs 21.4.12 which I use.

Wrong newsgroup then. comp.emacs.xemacs is that way ->...