Re: Major mode of orgweb/publish.sh?

[Max Nikulin <manikulin@gmail.com>]

On 14/04/2023 16:20, Ruijie Yu wrote:
> Ihor Radchenko writes:
>> Ruijie Yu writes:
>>> Major mode was erronously set to shell-script-mode because of the empty line.

Empty line was added by mistake, see "23.3 Choosing File Modes" in the 
Emacs manual:
(info "(emacs) Choosing Modes")
https://www.gnu.org/software/emacs/manual/html_node/emacs/Choosing-Modes.html
----
When the first line starts with ‘#!’, you usually cannot use the ‘-*-’
feature on the first line, because the system would get confused when
running the interpreter. So Emacs looks for ‘-*-’ on the second line in
such files as well as on the first line. The same is true for man pages
which start with the magic string ‘'\"’ to specify a list of troff
preprocessors.
----

>> The line in question is inline stdin redirect
>> in shell. "#..." is what is fed to exec emacs.

There is no stdin redirection,
":"; exec emacs --script "$0" #...
line instructs shell to stop interpreting this file and to execute emacs 
instead, passing file name for this script. This line is valid for both 
shell (sequence of "true" and "exec" commands) and elisp (string and 
comment). So this is a valid elisp file for emacs.

> I was about to propose changing the shbang line into just
> #!/usr/bin/emacs -x

It would fix path to emacs binary. Currently double trampoline is used. 
I see no point in /usr/bin/env since location of shell is considered 
fixed. That is why

#!/bin/sh

should work as well. Shell looks up for emacs in the $PATH environment 
variable. /usr/bin/env can do it as well, but shebang allows just single 
argument. Latest GNU env versions are able to split passed string to 
separate argument (-S option), but currently interpreting of script 
arguments as emacs options are suppressed by -- before "$@", so they are 
passed as `argv' list elements.

#!/usr/bin/env -S emacs --quick --script

should work, but it is less portable since relies on recent GNU env 
version and less safe since script options may modify emacs behavior.