2.4.5. ioctl FE_SET_PROPERTY, FE_GET_PROPERTY

2.4.5.1. Name

FE_SET_PROPERTY - FE_GET_PROPERTY - FE_SET_PROPERTY sets one or more frontend properties. - FE_GET_PROPERTY returns one or more frontend properties.

2.4.5.2. Synopsis

int ioctl(int fd, FE_GET_PROPERTY, struct dtv_properties *argp)

int ioctl(int fd, FE_SET_PROPERTY, struct dtv_properties *argp)

2.4.5.3. Arguments

fd

File descriptor returned by open().

argp

Pointer to struct dtv_properties.

2.4.5.4. Description

All Digital TV frontend devices support the FE_SET_PROPERTY and FE_GET_PROPERTY ioctls. The supported properties and statistics depends on the delivery system and on the device:

• FE_SET_PROPERTY:
  • This ioctl is used to set one or more frontend properties.
  • This is the basic command to request the frontend to tune into some frequency and to start decoding the digital TV signal.
  • This call requires read/write access to the device.

Note

At return, the values aren’t updated to reflect the actual parameters used. If the actual parameters are needed, an explicit call to FE_GET_PROPERTY is needed.

• FE_GET_PROPERTY:
  • This ioctl is used to get properties and statistics from the frontend.
  • No properties are changed, and statistics aren’t reset.
  • This call only requires read-only access to the device.

2.4.5.5. Return Value

On success 0 is returned.

On error -1 is returned, and the errno variable is set appropriately.

Generic error codes are described at the Generic Error Codes chapter.