Can a stream ID be passed to a function?

[JamesW]

Hi folks,

I'm writing an application which is going to have a local RS232 menu/diagnostic system on it, but also a remote one accessed by modem.

Ideally I'd like to write a single set of routines for it, that I pass the stream ID of the serial port to, which then automatically squirts data out the relevant port.

However I can't find any documentation on how to pass stream id's to functions.

something along the lines of

[RF_Developer]

You can't. That's why there's no documentation to say that you can.

"Streams" in CCS are not really streams, but just ID constants that differentiate between ports and devices at compile time only. They must be constants, they cannot be variables and they cannot be passed at runtime as parameters.

Even printf() and its relatives are not runtime functions, they are indications to the compiler to replace them by code that provides the relevant functionality. Indeed relatively few Cs actually have true runtime callable printf functions. The only one that I've ever encountered that actually implemented them as C functions (as opposed to assembler, or as CCS C as inline/called code) was a TI 320C6200 compiler.

So, instead you can assign some other ident, e.g numbers, and pass those with a switch in your "universal" IO routines.

[jgschmidt]

I've handled this in the past by preparing the data I want to output with sprintf() to a string. This handles all the complicated work in one place.
Then I have multiple fputs() functions to output the prepared data, one for each stream. An if or switch statement then decides which one to use.

Maybe not very pretty but it works, and that's what counts.
_________________
Jürgen
www.jgscraft.com

[JamesW]

Thanks guys,

Thought I was being over optimistic

Cheers

James

[Ttelmah]

Have a look at the answer I posted only a couple of days ago, in the thread 'passing variables in kbhit'. It explains 'why', but also how you can work round it.