Bash and C++, friends?

[Magnus Jonneryd]

Hi, I'm planning on writing a program that interactively is fed input via a
shell (bash). I also want to be able to write a shell script that executes
various commands related to my program. In short i want to provide input to
a program using some (or all) of the functionality found in bash.

It's mainly the format of the file I'm having trouble with. I wanted to be
able to write something like this:
#!/bin/bash

for x in xs
do
myprog.method(x )
done

How do i call myprog from a bash script (myprog is executing and reacting to
the input)?

Hopefully I've been able to convey my message.

Thanks in advance!

--
(Should insert humorous quotation here)

[Magnus Jonneryd]

Richard Herring wrote:

In message <43******@news. wineasy.se>, Magnus Jonneryd
<ma************ *@ipbolaget.com > writes

Richard Herring wrote:

In message <43******@news. wineasy.se>, Magnus Jonneryd
<ma************ *@ipbolaget.com > writes
Tom Felker wrote:

> On Sat, 13 Aug 2005 17:44:26 +0200, Magnus Jonneryd wrote:
>
>> Hi, I'm planning on writing a program that interactively is fed input
>> via a shell (bash). I also want to be able to write a shell script
>> that executes various commands related to my program. In short i want
>> to provide input to a program using some (or all) of the
>> functionality found in bash.
>>
>> It's mainly the format of the file I'm having trouble with. I wanted
>> to be able to write something like this:
>> #!/bin/bash
>>
>> for x in xs
>> do
>> myprog.method(x )
>> done
>>
>> How do i call myprog from a bash script (myprog is executing and
>> reacting to the input)?
>>
>> Hopefully I've been able to convey my message.
>>
>> Thanks in advance!
>
> Well, there's no way to directly call a method from a shell script.
> How
> you go about doing this indirectly depends on what you want. As
> someone
> else mentioned, one way is just command line arguments. If you need
> the functions to be called successively during one run of myprog,
> probably the best way is to make myprog be kind of a shell itself.
>
> The way you do this is, in the main() of myprog, have a loop that
> reads a line from standard input (gets(), cin.getline()) and call the
> associated
> function with the given arguments. Then, in a shell script, you can
> do something like:
>
> (
> echo init_method
> for x in xs; do
> echo method $x;
> done
> echo other_methods
> ) | myprog
>
> You could debug this by taking out the "| myprog" part, in which case
> the script will print to stdout what it would have given to your
> program. You can also test your program by just running it on its own
> and typing in your functions manually.
>
Ok, I thought that might be the case. Was hoping to avoid parsing but it
seems unavoidable. Well, well, thanks anyway.

I realize this might be the wrong forum, but I was thinking that it
might be possible to use Python instead of shell-scripts, any thoughts?

It sounds as though you're looking for a scripting language with a C++
(or C?) API so that you can embed a script interpreter within your
application and have it execute callbacks into your code when it finds
appropriate commands in the script. I don't know enough details to make
recommendations , but Python, Perl, Rexx, Ruby and similar script
interpreters might be possible candidates.

I was thinking along those lines and I've discovered the module/library
BOOST. Can someone that had some experience using it give me a quick
review i.e do you recommend it or not?

Boost is highly recommended - for what it does, but it's not what you're
looking for here. It's not a module but a collection of relatively
low-level algorithms and utilities. There are parts which would
certainly help if you wanted to write your own parser, but that would be
a *lot* of work compared with slotting in a ready-made interpreter.

Must have misinterpreted the info, sorry. Do you have an opinion about cint
or some other interpreter (preferably for C/C++ or Python)?
--
(Should insert humorous quotation here)

[Richard Herring]

In message <43******@news. wineasy.se>, Magnus Jonneryd
<ma************ *@ipbolaget.com > writes

Richard Herring wrote:

In message <43******@news. wineasy.se>, Magnus Jonneryd
<ma************ *@ipbolaget.com > writes

Richard Herring wrote:

In message <43******@news. wineasy.se>, Magnus Jonneryd
<ma************ *@ipbolaget.com > writes
>Tom Felker wrote:
>
>> On Sat, 13 Aug 2005 17:44:26 +0200, Magnus Jonneryd wrote:
>>
>>> Hi, I'm planning on writing a program that interactively is fed input
>>> via a shell (bash). I also want to be able to write a shell script
>>> that executes various commands related to my program. In short i want
>>> to provide input to a program using some (or all) of the
>>> functionality found in bash.
>>>
>>> It's mainly the format of the file I'm having trouble with. I wanted
>>> to be able to write something like this:
>>> #!/bin/bash
>>>
>>> for x in xs
>>> do
>>> myprog.method(x )
>>> done
>>>
>>> How do i call myprog from a bash script (myprog is executing and
>>> reacting to the input)?
>>>
>>> Hopefully I've been able to convey my message.
>>>
>>> Thanks in advance!
>>
>> Well, there's no way to directly call a method from a shell script.
>> How
>> you go about doing this indirectly depends on what you want. As
>> someone
>> else mentioned, one way is just command line arguments. If you need
>> the functions to be called successively during one run of myprog,
>> probably the best way is to make myprog be kind of a shell itself.
>>
>> The way you do this is, in the main() of myprog, have a loop that
>> reads a line from standard input (gets(), cin.getline()) and call the
>> associated
>> function with the given arguments. Then, in a shell script, you can
>> do something like:
>>
>> (
>> echo init_method
>> for x in xs; do
>> echo method $x;
>> done
>> echo other_methods
>> ) | myprog
>>
>> You could debug this by taking out the "| myprog" part, in which case
>> the script will print to stdout what it would have given to your
>> program. You can also test your program by just running it on its own
>> and typing in your functions manually.
>>
>Ok, I thought that might be the case. Was hoping to avoid parsing but it
>seems unavoidable. Well, well, thanks anyway.
>
>I realize this might be the wrong forum, but I was thinking that it
>might be possible to use Python instead of shell-scripts, any thoughts?

It sounds as though you're looking for a scripting language with a C++
(or C?) API so that you can embed a script interpreter within your
application and have it execute callbacks into your code when it finds
appropriate commands in the script. I don't know enough details to make
recommendations , but Python, Perl, Rexx, Ruby and similar script
interpreters might be possible candidates.
I was thinking along those lines and I've discovered the module/library
BOOST. Can someone that had some experience using it give me a quick
review i.e do you recommend it or not?

Boost is highly recommended - for what it does, but it's not what you're
looking for here. It's not a module but a collection of relatively
low-level algorithms and utilities. There are parts which would
certainly help if you wanted to write your own parser, but that would be
a *lot* of work compared with slotting in a ready-made interpreter.

Must have misinterpreted the info, sorry. Do you have an opinion about cint
or some other interpreter (preferably for C/C++ or Python)?

Sorry, I've no experience of any of them. Anyone else?

--
Richard Herring