tcsendbreak (BPX1TSB, BPX4TSB) — Send a break condition to a terminal

Function

The tcsendbreak callable service sends a BREAK signal to a terminal that uses asynchronous serial data transmission.

If the target terminal is an OCS-attached serial terminal, the BREAK signal is sent to the terminal. If the target terminal is a pseudoterminal (pty), control returns without any significant action.

Requirements

Operation	Environment
Authorization:	Supervisor or problem state, any PSW key
Dispatchable unit mode:	Task
Cross memory mode:	PASN = HASN
AMODE (BPX1TSB):	31-bit
AMODE (BPX4TSB):	64-bit
ASC mode:	Primary mode
Interrupt status:	Enabled for interrupts
Locks:	Unlocked
Control parameters:	All parameters must be addressable by the caller and in the primary address space.

Format

CALL BPX1TSB,(File_descriptor,
              Duration,
              Return_value,
              Return_code,
              Reason_code)

AMODE 64 callers use BPX4TSB with the same parameters.

Parameters

File_descriptor

Supplied parameter

Type:: Integer
Length:: Fullword

The name of a fullword that contains the file descriptor for the terminal device to which the break is to be sent.

Duration

Supplied parameter

Type:: Integer
Length:: Fullword

The name of a fullword that contains the duration of the BREAK transmission. If the target terminal is a pseudoterminal, the Duration parameter has no effect.

Return_value

Returned parameter

Type:: Integer
Length:: Fullword

The name of a fullword in which the tcsendbreak service returns 0 if the request is successful, or -1 if it is not successful.

Return_code

Returned parameter

Type:: Integer
Length:: Fullword

The name of a fullword in which the tcsendbreak service stores the return code. The tcsendbreak service returns Return_code only if Return_value is -1. For a complete list of possible return code values, see z/OS UNIX System Services Messages and Codes. The tcsendbreak service can return one of the following values in the Return_code parameter:

Return_code	Explanation
EBADF	File_descriptor is not a valid open file descriptor.
EINTR	The tcsendbreak (BPX1TSB, BPX4TSB) service was called from a background job, and the SIGTTOU signal either had default action or a signal handler. The function was not performed.
EIO	The process group of the process that is issuing the function is an orphaned, background process group, and the process that is issuing the function is not ignoring or blocking SIGTTOU.
ENOTTY	File_descriptor is not associated with a terminal.

Reason_code

Returned parameter

Type:: Integer
Length:: Fullword

The name of a fullword in which the tcsendbreak service stores the reason code. The tcsendbreak service returns Reason_code only if Return_value is -1. Reason_code further qualifies the Return_code value. For the reason codes, see z/OS UNIX System Services Messages and Codes.

Usage notes

The following table defines the processing of the SIGTTOU signal when tcsendbreak is called from a background process against a controlling terminal:

SIGTTOU processing	Expected behavior
Default or signal handler	The SIGTTOU signal is generated. The function is not performed. Return_value is set to -`1`, and Return_code is set to EINTR.
Ignored or blocked	The SIGTTOU signal is not sent. The function continues normally.

tcsendbreak (BPX1TSB, BPX4TSB) — Send a break condition to a terminal

Function

Requirements

Format

Parameters

Usage notes

Related services

Characteristics and restrictions

Examples