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drv_getparm(9f) [debian man page]

drv_getparm(9F) 					   Kernel Functions for Drivers 					   drv_getparm(9F)

NAME
drv_getparm - retrieve kernel state information SYNOPSIS
#include <sys/ddi.h> int drv_getparm(unsigned int parm, void *value_p); INTERFACE LEVEL
Architecture independent level 1 (DDI/DKI). PARAMETERS
parm The kernel parameter to be obtained. Possible values are: "small and bold"ReadLTthe value of lbolt. lbolt is a clock_t that is unconditionally incremented by one at each clock tick. No special treatment is applied when this value overflows the maximum value of the signed integral type clock_t. When this occurs, its value will be negative, and its magnitude will be decreasing until it again passes zero. It can therefore not be relied upon to provide an indication of the amount of time that passes since the last system reboot, nor should it be used to mark an absolute time in the system. Only the difference between two measurements of lbolt is significant. It is used in this way inside the system kernel for timing purposes. PPGRP Read the process group identification number. This number determines which processes should receive a HANGUP or BREAK signal when detected by a driver. UPROCP Read the process table token value. PPID Read process identification number. PSID Read process session identification number. TIME Read time in seconds. UCRED Return a pointer to the caller's credential structure. value_p A pointer to the data space in which the value of the parameter is to be copied. DESCRIPTION
Since the release of the Solaris 2.6 operating environment, the drv_getparm() function has been replaced by ddi_get_lbolt(9F), ddi_get_time(9F), and ddi_get_pid(9F). drv_getparm() function verifies that parm corresponds to a kernel parameter that may be read. If the value of parm does not correspond to a parameter or corresponds to a parameter that may not be read, -1 is returned. Otherwise, the value of the parameter is stored in the data space pointed to by value_p. drv_getparm() does not explicitly check to see whether the device has the appropriate context when the function is called and the function does not check for correct alignment in the data space pointed to by value_p. It is the responsibility of the driver writer to use this function only when it is appropriate to do so and to correctly declare the data space needed by the driver. RETURN VALUES
drv_getparm() returns 0 to indicate success, -1 to indicate failure. The value stored in the space pointed to by value_p is the value of the parameter if 0 is returned, or undefined if -1 is returned. -1 is returned if you specify a value other than LBOLT, PPGRP, PPID, PSID, TIME, UCRED, or UPROCP. Always check the return code when using this function. CONTEXT
drv_getparm() can be called from user context only when using PPGRP, PPID, PSID, UCRED, or UPROCP. It can be called from user or interrupt context when using the LBOLT or TIME argument. SEE ALSO
ddi_get_lbolt(9F), ddi_get_pid(9F), ddi_get_time(9F), buf(9S) Writing Device Drivers SunOS 5.10 24 Jun 1997 drv_getparm(9F)

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putctl(9F)						   Kernel Functions for Drivers 						putctl(9F)

NAME
putctl - send a control message to a queue SYNOPSIS
#include <sys/stream.h> int putctl(queue_t *q, int type); INTERFACE LEVEL
Architecture independent level 1 (DDI/DKI). PARAMETERS
q Queue to which the message is to be sent. type Message type (must be control, not data type). DESCRIPTION
The putctl() function tests the type argument to make sure a data type has not been specified, and then attempts to allocate a message block. putctl() fails if type is M_DATA, M_PROTO, or M_PCPROTO, or if a message block cannot be allocated. If successful, putctl() calls the put(9E) routine of the queue pointed to by q with the newly allocated and initialized messages. RETURN VALUES
On success, 1 is returned. If type is a data type, or if a message block cannot be allocated, 0 is returned. CONTEXT
The putctl() function can be called from user, interrupt, or kernel context. EXAMPLES
Example 1 Using putctl() The send_ctl() routine is used to pass control messages downstream. M_BREAK messages are handled with putctl() (line 11). putctl1(9F) (line 16) is used for M_DELAY messages, so that parm can be used to specify the length of the delay. In either case, if a message block cannot be allocated a variable recording the number of allocation failures is incremented (lines 12, 17). If an invalid message type is detected, cmn_err(9F) panics the system (line 21). 1 void 2 send_ctl(wrq, type, parm) 3 queue_t *wrq; 4 uchar_t type; 5 uchar_t parm; 6 { 7 extern int num_alloc_fail; 8 9 switch (type) { 10 case M_BREAK: 11 if (!putctl(wrq->q_next, M_BREAK)) 12 num_alloc_fail++; 13 break; 14 15 case M_DELAY: 16 if (!putctl1(wrq->q_next, M_DELAY, parm)) 17 num_alloc_fail++; 18 break; 19 20 default: 21 cmn_err(CE_PANIC, "send_ctl: bad message type passed"); 22 break; 23 } 24 } SEE ALSO
put(9E), cmn_err(9F), datamsg(9F), putctl1(9F), putnextctl(9F) Writing Device Drivers STREAMS Programming Guide SunOS 5.11 16 Jan 2006 putctl(9F)
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