rtinrepos

Typically it is used in the INSTRUMENT::run() member function of an instrument. It only works on file input, as arbitrary movement forwards and backwards in real-time isn't quite possible (yet).

It replaces the older inrepos function used in disk-only cmix.

Usage

int rtinrepos(Instrument *inst, int nframes, int whence)


*inst is a pointer to the INSTRUMENT object being scheduled. Usually this is the token this (i.e. a pointer to the INSTRUMENT calling the rtinrepos() function).
nframes is the number of samples to move the input pointer forwards or backwards from a point set by whence. nframes can take a negative value.
whence works the same way that the unix lseek() function does:


• If whence is SEEK_SET, then the input read pointer will be set nframes from the beginning of the soundfile.
• If whence is SEEK_CUR, the the input read pointer will be set nframes from the current read position (positive or negative values).
  
  [note: The values of SEEK_SET and SEEK_CUR are defined in the system header file "unistd.h". SEEK_END is not defined for use by rtinrepos().]
  


The rtinrepos() function returns 0 if it is successful, it will exit if there is an error.

Examples

#include <Instrument.h>
#include <unistd.h>

float in[];

int MYINSTRUMENT::run()
{
	int rsamps;
	int somenumber;

	...

	

	if (in == NULL) // first time, we need to allocate the buffer memory
		in = new float[RTBUFSAMPS*inputChannels()]
	rsamps = framesToRun() * inputChannels();

	rtinrepos(this, somenumber, SEEK_CUR);
	rtgetin(in, this, rsamps);

	...
}

See Also

• rtgetin