Function

ioctl invokes the w_ioctl service to issue ioctl commands to a file.

Restriction: Hierarchical file system files and pipes do not support ioctl commands.

Parameters

fd

A file descriptor for an open file.

Restriction: REXX does not support ioctl commands for sockets.

command

The numeric value for an ioctl command. The commands that can be specified vary by device and are defined by the device driver.

buffer

The name of a buffer containing the argument to be passed to the device driver. The argument is limited to 1024 bytes.

length

An optional numeric value indicating the length of the argument. If length is not specified, the length of the buffer is used.