sethostid()--Set Host ID
Syntax
#include <sys/types.h> #include <sys/socket.h> int sethostid(int host_id)
Service Program Name: QSOSRV1
Default Public Authority: *USE
Threadsafe: Yes
The sethostid() function is used to set a host ID.
Parameters
- host_id
- (Input) The 32-bit host_id
Authorities
No authorization is required.
Return Value
sethostid() returns an integer. Possible values are:
- -1 (unsuccessful)
- 0 (successful)
Error Conditions
When sethostid() fails, errno can be set to one of the following:
| [EIO] | Input/output error. |
| [EPERM] | Operation not permitted.
The process does not have the appropriate privileges to use sethostid(). |
| [EUNKNOWN] | Unknown system state. |
Error Messages
| Message ID | Error Message Text |
|---|---|
| CPE3418 E | Possible APAR condition or hardware failure. |
| CPF9872 E | Program or service program &1 in library &2 ended. Reason code &3. |
| CPFA081 E | Unable to set return value or error code. |
Usage Notes
- A process must have the *iosyscfg special authority to use the
sethostid().
- When a process issues a sethostid(), the host_id can be
accessed by ANY process that issues a gethostid().
- While many socket implementations refer to the host_id as the IP
address of the machine, this is not necessarily the case. Many machines that
support the TCP/IP protocol suite support multiple local IP addresses. The
value contained in host_id is not used by TCP in any
manner.
- The host_id is reset to zero when an initial program load is
performed.
- The host_id is a signed integer. Therefore, a user should be careful to not confuse a return value of -1 from a gethostid() with an error return value. gethostid() never returns an error.
Related Information
gethostid()--Retrieve Host ID Address
API introduced: V3R1