From: Andrew Walrond <andrew@...>
Date: 2004-06-29T04:22:27+09:00
Subject: system() shouldn't throw exceptions, should it?

While building a Rubyx distro (the build script is written in ruby) a user has 
reported this error:

>
> Making 'whatis' database...
>
> Unmounting proc
> /mnt/rubyx/rubyx-76/rubyx:946:in `system': No such file or directory -
> makewhatis /man (Errno::ENOENT)
>         from /mnt/rubyx/rubyx-76/rubyx:946:in `install'
>         from /mnt/rubyx/rubyx-76/rubyx:800:in `each'
>         from /mnt/rubyx/rubyx-76/rubyx:800:in `install'
>         from /mnt/rubyx/rubyx-76/rubyx:1492
>         from /mnt/rubyx/rubyx-76/rubyx:1087:in `catch'
>         from /mnt/rubyx/rubyx-76/rubyx:1087
> root@aydindril:/mnt/rubyx/linux-2.6.7/linux-2.6.7#

The bit of code running  here looks like this:

if $root=='/'
        puts("Making 'whatis' database...")
        system("makewhatis /man")
end

Now makewhatis is not available, but the system() command has thrown an 
exception, which shouldn't happen (should it?).

According to ri system,

--------------------------------------------------------- Kernel::system
     system( aCmd [, args]* ) -> true or false
------------------------------------------------------------------------
     Executes aCmd in a subshell, returning true if the command was
     found and ran successfully, false otherwise. A detailed error code
     is available in $?. The arguments are processed in the same way as
     for Kernel::exec on page 419.

So on failure it should just return false?

Am I reading this correctly? Could this be ruby version specific?

Andrew Walrond