Re: Redirecting standard output to a file

[address@hidden]

On 29 Jun., 13:15, Michael Hopkins <michael.hopk...@-rm-this-hopkins-
research.com> wrote:
> Hi all
>
> I have a question about using the classes in base to redirect standard
> output to a file without too much hassle or re-writing of code.  I have
> classes that print themselves to standard output like this:
>
>         [ someObject show ];
>
> ..but would like to be able to redirect this behaviour within code and
> possibly in response to user input.  Something like...
>
>         [ outputFile appendedWith:[ someObject show ]];
>
> I suspect that NSPipe and/or NSFileHandle might be involved but welcome
> any tips.
>
> TIA
>
> Michael
>
> --
> ______________________________________________
>
>     Hopkins Research      Touch the Future
> ______________________________________________

Some de-facto standard is that objects derived from NSObject should
respond to - (NSString *) description which returns a user-readable
description.

Then, you can write

[[NSFileHandle fileHandleWithStandardOutput] writeData:[[object
description] dataUsingEncoding:NSUTF8StringEncoding]];

If you prefer to mix OpenSTEP and POSIX:

printf("%s\n", [[object description] UTF8String]);

You could also pack that into a Macro (similar to NSLog which first
builds a formatted string and then writes to StandardErrlr).

What you also could do in main():

freopen(stdout, "path to file", "w");

-- hns