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putctl(9f) [bsd man page]

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
putctl() 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
putctl() can be called from user or interrupt 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 5.10 11 Apr 1991 putctl(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
putctl() 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
putctl() can be called from user or interrupt 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 5.10 11 Apr 1991 putctl(9F)

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