On Tue, Jan 10, 2017 at 2:58 PM, Scott scottro@nyc.rr.com
[LINUX_Newbies] <LINUX_Newbies@yahoogroups.com> wrote:
>
> The answer is that most things run on the BSDs, but not all, and they
> frequently have to be somewhat re-written.
More specifically, anything that runs via an interpreter should be ok
in MOST cases (caveat emptor) such as Java, Python, etc.
Things that directly make system calls directly should (again caveat
emptor) work if they adhere to POSIX standards, and things that make
non-POSIX system calls will need porting.
A good demonstration of this (using an interpreted language and
without diving into compiled code that I haven't written in forever)
is the following, very simple code:
bladernr@galactica:~/development$ cat bashtest.sh
# test of a bashism, run this in bash and in sh to see the difference
function bash_function { echo I only work in BASH; }
posix_function() { echo I work in any POSIX shell; }
bash_function || echo Y U NO WRITE POSIX CODE???!?
posix_function || echo Y UR POSIX EXAMPLE FULL OF FAIL!???
bladernr@galactica:~/development$ bash bashtest.sh
I only work in BASH
I work in any POSIX shell
bladernr@galactica:~/development$ sh bashtest.sh
bashtest.sh: 3: bashtest.sh: function: not found
bashtest.sh: 7: bashtest.sh: bash_function: not found
Y U NO WRITE POSIX CODE???!?
I work in any POSIX shell
bladernr@galactica:~/development$ dash bashtest.sh
bashtest.sh: 3: bashtest.sh: function: not found
bashtest.sh: 7: bashtest.sh: bash_function: not found
Y U NO WRITE POSIX CODE???!?
I work in any POSIX shell
Note that posix_function works in all three, where bash_function is
not POSIX compliant and only works in BASH.
Cheers,
Jeff
Posted by: J <dreadpiratejeff@gmail.com>
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