Re: multi-threaded compiling

[Mischa Baars]

Which sort of brings us back to the original question I suppose. Who does
that line of code function from a script and why does it fail from the
command line? My guess was that the same thing makes this line fail from
the Makefile.

On Mon, Mar 11, 2024 at 7:46 PM Mischa Baars <mjbaars1977.backup@gmail.com>
wrote:

> You mean:
>
> for (( i=0; i<32; i++ )); do exit $i & wait -n; echo $?; done;
>
> with one command and one wait in a single loop. And this does execute on
> the command line. How interesting!
>
> for (( i=0; i<32; i++ )); do exit $i; done; for (( i=0; i<32; i++ )); do
> wait -n; echo $?; done;
>
> Because this doesn't and to be honest, I needed the pid and its index to
> retrieve gcc's output from a log file array afterwards.
>
> On Mon, Mar 11, 2024 at 7:25 PM alex xmb sw ratchev <fxmbsw7@gmail.com>
> wrote:
>
>>
>>
>> On Mon, Mar 11, 2024, 19:22 Mischa Baars <mjbaars1977.backup@gmail.com>
>> wrote:
>>
>>> On Mon, Mar 11, 2024 at 6:22 PM alex xmb sw ratchev <fxmbsw7@gmail.com>
>>> wrote:
>>>
>>>> i also completly dont get ur issue
>>>>
>>>> f=( a.c b.c .. ) threads=$( nproc ) i=-1 r=
>>>>
>>>>   while [[ -v f[++i] ]] ; do
>>>>  (( ++r > threads )) &&
>>>> wait -n
>>>> gcc -c "${f[i]}" &
>>>>   done
>>>>
>>>
>>> How nice!
>>>
>>> wait -n exit 1 & echo $?
>>>
>>
>> doesnt need a pid
>> 1 : 1 as i wrote it , excepts add 'wait' as new last line
>>
>> You got me the solution :) Except that wait expects a pid after -n.
>>>
>>> Maybe
>>>
>>> for (( i=0; i<32; i++ )); do exit 1 & wait -n $!; echo $?; done;
>>>
>>> is what you meant? The equivalence of sequential execution?
>>>
>>> First think, then do magic.
>>>
>>>
>>>>
>>>>
>>>
>>>>
>>>> On Mon, Mar 11, 2024, 18:16 Mischa Baars <mjbaars1977.backup@gmail.com>
>>>> wrote:
>>>>
>>>>> Hello Paul,
>>>>>
>>>>> It seems I'm awake a little longer than you are.
>>>>>
>>>>> The second paragraph as you see it, belongs to 1)
>>>>> The fourth paragraph as you see it, belongs to 2)
>>>>>
>>>>> The actual command invocations (a Makefile, a make.sh script) can be
>>>>> found
>>>>> in the attachment, as indicated on the first line of the mail. In the
>>>>> attachment there are two directories, one and two, belonging to 1) and
>>>>> 2)
>>>>> respectively.
>>>>>
>>>>> I'm not into Vulcan mindmelds, so I hope everything from the first mail
>>>>> makes sense to you and everyone on this mailing list now.
>>>>>
>>>>> Best regards,
>>>>> Mischa Baars.
>>>>>
>>>>> On Mon, Mar 11, 2024 at 5:01 PM Paul Smith <psmith@gnu.org> wrote:
>>>>>
>>>>> > On Mon, 2024-03-11 at 09:56 +0100, Mischa Baars wrote:
>>>>> > > I've attached the problem. It consists of two parts:
>>>>> > >
>>>>> > > 1) multi-threaded bash script and / or multi-threaded Makefile
>>>>> > >
>>>>> > > Running bash script functions as expected, but executing the same
>>>>> > > line of code with make and / or the command line, does not
>>>>> function.
>>>>> > > Perhaps someone could explain to me why?
>>>>> > >
>>>>> > > 2) passing a string argument from a bash script and / or Makefile
>>>>> to
>>>>> > > the gcc -D option
>>>>> > >
>>>>> > > Running the makefile functions as expected, but I have not been
>>>>> able
>>>>> > > to get similar code to work from a bash script. Can someone please
>>>>> > > explain to me what I'm doing wrong?
>>>>> >
>>>>> > I don't understand the problem.  In the third paragraph above you say
>>>>> > the bash script works as expected and the makefile doesn't work, but
>>>>> in
>>>>> > the last paragraph you say that the makefile works as expected but
>>>>> you
>>>>> > can't get it to work in bash.
>>>>> >
>>>>> > Please provide actual command invocations (cut and pasted) showing
>>>>> the
>>>>> > output you received and explaining exactly what is wrong with it.
>>>>> >
>>>>> > But before you do that, be aware that make does NOT invoke /bin/bash
>>>>> as
>>>>> > its shell.  It invokes /bin/sh.  On some systems /bin/sh is actually
>>>>> an
>>>>> > alias for bash.  On other systems it isn't.
>>>>> >
>>>>> > If you want your makefile to always use bash as its shell, you should
>>>>> > add an explicit:
>>>>> >
>>>>> >     SHELL := /bin/bash
>>>>> >
>>>>> > to your makefile to force it.  Maybe that will solve your problem.
>>>>> If
>>>>> > not we'll need details such as I mention above.
>>>>> >
>>>>>
>>>>