Open Sound System
OSS 4.x Programmer's Guide

Do you have problems with sound/audio application development? Don't panic! Click here for help!

SNDCTL_DSP_SETSYNCRO

Slaves the audio device to the /dev/sequencer driver (obsolete)

Usage

ioctl(fd, SNDCTL_DSP_SETSYNCRO, NULL);

The above code fragment lacks all error checks for clarity. Real world applications must always check for the errors and handle them as described below. Also most OSS ioctl calls will return information in the argument variable and it's usually necessary to check it too.

Description

This ioctl call slaves the audio device to the /dev/sequencer driver. In this way the audio playback will not start before some other application triggers it using the SEQ_PLAYAUDIO() or SEQ_PLAYAUDIO2() macros. There is no idea in using this call since the /dev/sequencer interface is no longer actively used. Use SNDCTL_DSP_SYNCGROUP call will replace this one in the future OSS versions.

Compatibility issues

This call is supported only by certain older OSS versions.

OSS ioctl return values

The return value from the OSS ioctl calls will be -1 if a fatal error occurred. Other values mean that the ioctl call was more or less successful. However in most cases the application must check the value returned in the argument to see what was the accepted value.

Please see the Possible error codes (errno) returned by OSS calls section for more info about the error codes returned by OSS.

Sample programs

No sample programs available