tcgetpgrp (BPX1TGP, BPX4TGP) — Get the foreground process group ID
Function
The tcgetpgrp callable service gets the process group ID of the foreground process group that is associated with a terminal, which is identified by its file descriptor.
Requirements
Operation | Environment |
---|---|
Authorization: | Supervisor or problem state, any PSW key |
Dispatchable unit mode: | Task |
Cross memory mode: | PASN = HASN |
AMODE (BPX1TGP): | 31-bit |
AMODE (BPX4TGP): | 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
|
AMODE 64 callers use BPX4TGP 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.
- Return_value
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword in which the tcgetpgrp service returns the process group ID of the foreground process group that is associated with the terminal, if the request is successful; or -1, if it is not successful. If there is no foreground process group, a positive value, not equal to any existing process group, is returned.
- Return_code
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword in which the tcgetpgrp service stores the return code. The tcgetpgrp 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 tcgetpgrp service can return one of the following values in the Return_code parameter:Return_code Explanation EBADF The File_descriptor parameter does not specify a valid open file descriptor. ENOTTY The file descriptor is not associated with a terminal. - Reason_code
- Returned parameter
- Type:
- Integer
- Length:
- Fullword
The name of a fullword in which the tcgetpgrp service stores the reason code. The tcgetpgrp 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.
Related services
Characteristics and restrictions
There are no restrictions on the use of the tcgetpgrp service.
Examples
For an example using this callable service, see BPX1TGP (tcgetpgrp) example.