[PATCH] guile-readline: Use an empty string if HOME is unset

[PATCH] guile-readline: Use an empty string if HOME is unset

[David Michael]

* guile-readline/ice-9/readline.scm (history-file): When the HOME
  environment variable is unset, use the empty string in its place.
---

Hi,

If a Guile program uses the readline module without setting HOME, it
will fail due to string-append getting a #f argument.  In particular,
this necessitates workarounds when starting GNU dmd early in the boot
process.  To illustrate this, try:

    guile -c '(use-modules (ice-9 readline))(display "working\n")'

And then:

    env -u HOME \
    guile -c '(use-modules (ice-9 readline))(display "working\n")'

Let me know if there is a better alternative for handling this case, and
I can send another patch.

Thanks.

David


 guile-readline/ice-9/readline.scm | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/guile-readline/ice-9/readline.scm b/guile-readline/ice-9/readline.scm
index 02e68af..0979fd3 100644
--- a/guile-readline/ice-9/readline.scm
+++ b/guile-readline/ice-9/readline.scm
@@ -119,7 +119,8 @@
 (define-once the-readline-port #f)
 
 (define-once history-variable "GUILE_HISTORY")
-(define-once history-file (string-append (getenv "HOME") "/.guile_history"))
+(define-once history-file
+  (string-append (or (getenv "HOME") "") "/.guile_history"))
 
 (define-public readline-port
   (let ((do (lambda (r/w)
-- 
1.9.3

Re: [PATCH] guile-readline: Use an empty string if HOME is unset

[Eli Zaretskii]

> From: David Michael <fedora.dm0@gmail.com>
> Date: Tue, 09 Sep 2014 17:28:42 -0400
> 
> -(define-once history-file (string-append (getenv "HOME") "/.guile_history"))
> +(define-once history-file
> +  (string-append (or (getenv "HOME") "") "/.guile_history"))

Is there any guarantee that the root directory will be writable?

How about "./.guile_history" instead?

Re: [PATCH] guile-readline: Use an empty string if HOME is unset

[David Michael]

On Wed, Sep 10, 2014 at 1:00 PM, Eli Zaretskii <eliz@gnu.org> wrote:
>> From: David Michael <fedora.dm0@gmail.com>
>> Date: Tue, 09 Sep 2014 17:28:42 -0400
>>
>> -(define-once history-file (string-append (getenv "HOME") "/.guile_history"))
>> +(define-once history-file
>> +  (string-append (or (getenv "HOME") "") "/.guile_history"))
>
> Is there any guarantee that the root directory will be writable?
>
> How about "./.guile_history" instead?

That is okay with me.  Do you want a new patch with s/""/"."/ and
s/empty string/current directory/?

Thanks.

David

P.S.  I resent the patch to bug-guile earlier so it got a bug number.
It's #18439.  Sorry for double-posting.

Re: [PATCH] guile-readline: Use an empty string if HOME is unset

[Eli Zaretskii]

> Date: Wed, 10 Sep 2014 14:06:15 -0400
> From: David Michael <fedora.dm0@gmail.com>
> Cc: guile-devel@gnu.org
> 
> > How about "./.guile_history" instead?
> 
> That is okay with me.  Do you want a new patch with s/""/"."/ and
> s/empty string/current directory/?

Please wait for others to chime in.  I'm not speaking for the Guile
project, I just expressed my opinion on this.

Thanks.

Re: [PATCH] guile-readline: Use an empty string if HOME is unset

[Mark H Weaver]

David Michael <fedora.dm0@gmail.com> writes:
> * guile-readline/ice-9/readline.scm (history-file): When the HOME
>   environment variable is unset, use the empty string in its place.

FYI, this was discussed at <http://bugs.gnu.org/18439>, and we decided
to have guile-readline put .guile_history in the current directory
instead of the filesystem root when neither HOME nor GUILE_HISTORY are
found in the environment.

It's now pushed to stable-2.0, commit
3a3316e200ac49f0e8e9004c233747efd9f54a04.

    Thanks,
      Mark