I read:

I'm slightly confused about how pd handles files, because as it seems to me there are several operators to load files, but I don't know which one's the correct one for reading from a channel.

If I assume correctly that you are trying to process live input you should use the adc~ object which has 2 signal outlets for the right and left channel.

Second, whenever I connect more than two functions with each other they don't seem to work anymore, which is mainly because I don't know what input/output they assume (and the help files don't seem to know either), resulting mostly in errors.

the status window and the tutorial patches in the doc directory should get you started here, basically fft~ puts out numbers suitable for consumption of the ifft~ object, there are tutorial patches on that.

Finally, I would like to send the results to a C program: is there anything that allows me to do that other than writing things to a file, and opening it from the 'main' program?

there are netsend/receive objects that enable communication via sockets (tcp or udp) , on unix a named pipe (mknod /tmp/mypipe p) would be another option, writing an external hmmm .. anything else ?

lg

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