GNU Info

Info Node: (autotype)Executables

(autotype)Executables


Next: Timestamps Prev: Copyrights Up: Top
Enter node , (file) or (file)node

Making Interpreter Scripts Executable
*************************************

   Various interpreter modes such as Shell script mode or AWK mode will
automatically insert or update the buffer's magic number, a special
comment on the first line that makes the `exec' systemcall know how to
execute the script.  To this end the script is automatically made
executable upon saving, with `executable-chmod' as argument to the
system `chmod' command.  The magic number is prefixed by the value of
`executable-prefix'.

   Any file whose name matches `executable-magicless-file-regexp' is not
furnished with a magic number, nor is it made executable.  This is
mainly intended for resource files, which are only meant to be read in.

   The variable `executable-insert' says what to do when
`executable-set-magic' is called non-interactively, e.g. when file has
no or the wrong magic number:
`nil'
     Do nothing.

`t'
     Insert or update magic number.

other
     Insert or update magic number, but mark as unmodified.

   The variable `executable-query' controls whether to ask about
inserting or updating the magic number.  When this is `nil' updating is
only done with `M-x executable-set-magic'.  When this is `function' you
are queried whenever `executable-set-magic' is called as a function,
such as when Emacs puts a buffer in Shell script mode.  Otherwise you
are alway queried.

   `M-x executable-self-display' adds a magic number to the buffer,
which will turn it into a self displaying text file, when called as a
Un*x command.  The "interpreter" used is `executable-self-display' with
argument `+2'.


automatically generated by info2www version 1.2.2.9