man pages section 2: System Calls

uadmin(2)

Name

uadmin– administrative control

Synopsis

#include <sys/uadmin.h>

int uadmin(int cmd, int fcn, uintptr_t mdep);

Description

The uadmin() function provides control for basic administrative functions. This function is tightly coupled to the system administrative procedures and is not intended for general use. The argument mdep is provided for machine-dependent use and is not defined here. It should be initialized to NULL if not used.

As specified by cmd, the following commands are available:

A_SHUTDOWN

The system is shut down. All user processes are killed, the buffer cache is flushed, and the root file system is unmounted. The action to be taken after the system has been shut down is specified by fcn. The functions are generic; the hardware capabilities vary on specific machines.

AD_HALT: Halt the processor(s).
AD_POWEROFF: Halt the processor(s) and turn off the power.
AD_BOOT: Reboot the system, using the kernel file.
AD_IBOOT: Interactive reboot; user is prompted for bootable program name.

A_REBOOT

The system stops immediately without any further processing. The action to be taken next is specified by fcn as above.

A_DUMP

The system is forced to panic immediately without any further processing and a crash dump is written to the dump device (see dumpadm(1M)). The action to be taken next is specified by fcn, as above.

A_REMOUNT

The root file system is mounted again after having been fixed. This should be used only during the startup process.

A_FREEZE

Suspend the whole system. The system state is preserved in the state file. The following subcommands, specified by fcn, are available.

AD_COMPRESS: Save the system state to the state file with compression of data.
AD_CHECK: Check if your system supports suspend and resume. Without performing a system suspend/resume, this command checks if this feature is currently available on your system.
AD_FORCE: Force AD_COMPRESS even when threads of user applications are not suspendable.

Return Values

Upon successful completion, the value returned depends on cmd as follows:

A_SHUTDOWN: Never returns.
A_REBOOT: Never returns.
A_FREEZE: 0 upon resume.
A_REMOUNT: 0.

Otherwise, -1 is returned and errno is set to indicate the error.

Errors

The uadmin() function will fail if:

EBUSY: Suspend is already in progress.
EINVAL: The cmd argument is invalid.
ENOMEM: Suspend/resume ran out of physical memory.
ENOSPC: Suspend/resume could not allocate enough space on the root file system to store system information.
ENOTSUP: Suspend/resume is not supported on this platform or the command specified by cmd is not allowed.
ENXIO: Unable to successfully suspend system.
EPERM: The {PRIV_SYS_CONFIG} privilege is not asserted in the effective set of the calling process.

Warnings

Shutting down or halting the system by means of uadmin(1M) does not update the boot archive. Avoid using this command after

editing of files such as /etc/system
installing new driver binaries or kernel binaries
updating existing driver binaries or kernel binaries.

Use reboot(1M) or halt(1M) instead.

SunOS 5.10 Last Revised 10 Jul 2009