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ChannelCtl(), ChannelCtl_r()
Change the properties of a channel

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ChannelCtl(), ChannelCtl_r()

QNX SDP8.0C Library ReferenceAPIDeveloper

Change the properties of a channel

Synopsis:

#include <sys/neutrino.h>

int ChannelCtl( int chid
                int cmd
                void * data);

int ChannelCtl_r( int chid
                  int cmd
                  void * data );

Arguments:

chid

The channel ID of the channel.

cmd

The command you want to execute:

_NTO_CCTL_PULSE_POOL — Create a pulse pool associated with the channel. The data must point to a struct nto_channel_config.

data

A pointer to data associated with the specific command.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The ChannelCtl() and the ChannelCtl_r() kernel calls are used to configure a channel based on the provided command. The supported commands are:

_NTO_CCTL_PULSE_POOL — Configure the pulse pool of a pulse-pool channel.

Returns:

Both functions return 0 on success. If an error occurs:

ChannelCtl() returns -1 and set errno.
ChannelCtl_r() returns an error value from the Errors section and doesn't set errno.

Errors:

EBUSY

The channel is already associated with a pulse pool.

EINVAL

One of the following occurred:

The channel wasn't created with the _NTO_CHF_PULSE_POOL flag.
The number of pulses is invalid.

ENOMEM

There wasn't enough memory to create the pulse pool.

ENOSYS

The command provided isn't supported.

ESRCH

The chid (channel ID) doesn't identify an existing channel.

Classification:


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 11, 2025