Re: [Bug-apl] #!apl

[Juergen Sauermann]

Hi Hudson,

aas far as I know you can use a relative path to apl as long as the apl binary is in your
$PATH. Thus '#!apl --script' probably works regardless of whether apl is
installed in /usr/loccal/bin or in /user/bin.

However, my own personal experience with relative paths is quite negative and
troubleshooting problems caused by relative paths can be rather time-consuming.
So one of my golden rules (another one mentioned earlier) is: "always prefer
absolute paths over relative paths".

The reason for #! comes from man(2) execve.

/// Jürgen

On 08/21/2018 03:24 PM, Hudson Flavio Meneses Lacerda wrote:

Hi Jürgen,

Indeed, for my own local computer, I could install apl in /usr.

However, I also use third-part computers as restricted user ($), with apl installed in
a different path (under ~/).

Here is my new approach (trying to avoid side effects):

---8<----------------------------------
#!/bin/bash
'true' ⎕EA ''⍝;exec apl -s -f "$0" "$@"
⍝--------------------------------------
'⍝ Body of script'
   ⎕RL←×/⎕TS~0
   ?⍨ 20
'⍝ End of script'
)off
---------------------------------->8---

(That can work fine with bash or dash, but not with sash.)

By the way, why APL files need to start with "#!" to be accept by
)copy/load?

Cheers,
Hudson




On Tue, 21 Aug 2018 11:14:30 +0200
Juergen Sauermann <address@hidden> wrote:

Hi Hudson,

you can ./configure GNU APL with prefix=/usr and then recompile and
install.

/// Jürgen


On 08/21/2018 03:34 AM, Hudson Flavio Meneses Lacerda wrote:
Hi.

Some of my scripts use `#!/usr/bin/apl --script` (from Debian), but
now I am using SVN, so I should use `#!/usr/local/bin/apl --script`.
So, I need to change the scripts, that may be incompatible with
different environments…

I have tried:

#!/usr/bin/env apl
#!apl --script
#!/usr/bin/apl --script
#!/usr/local/bin/apl --script

So far, the best solution I could find (so that I do not need to
change the files in the future) is this file header:

----------------------------------------------------
#!
true ← ~false ← 0 ⍝; exec apl --script "$0" "$@"
----------------------------------------------------

Are there any better solutions?

Thanks,
Hudson