Re: Reduce startup time for script processing?

[Carlo De Falco]

> Il giorno 04 lug 2019, alle ore 11:14, Carlo De Falco <address@hidden> ha 
> scritto:
> 
> 
> 
>> Il giorno 04 lug 2019, alle ore 09:26, Andreas Weber <address@hidden> ha 
>> scritto:
>> 
>> Dear all,
>> 
>> I'm using GNU Octave 3.8.2 on an embedded system (RPi3) to execute
>> scripts and print the results multiple times.
>> 
>> foo.m:
>> printf ("bar\n")
>> 
>> $ octave -f --no-gui foo.m
>> 
>> This takes 1,3s on my system. Is there anything I can do to reduce the
>> "startup" time? Preload Octave into RAM? It would be okay if the first
>> start is slow and the subsequent runs are fast.
>> 
>> Thank you, Andy
> 
> 
> This is just a guess, I'm not actually sure it would be any better, but you 
> could maybe try keep octave running and communicate via a named pipe?

oops, you also need to create the named pipe!

> 
> foo.m:
> 
> #!/path/to/octave-cli -fq
> 
> fname = argv{1};
> while true
>  fid = fopen (fname, "r");
>  a = fgetl (fid);
>  if (a != -1)
>    disp (a)
>  endif
>  fclose (fid);
>  pause (.1)   
> endwhile 
> 
$ mkfifo -m a+rw tmpfile
> 
> $ chmod u+x ./foo.m &
> $ ./foo.m tmpfile
> $ echo bar >> tmpfile
> $ echo bar >> tmpfile
> 
> HTH,
> c.