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stack_base--ÐÂÏ̵߳ĶÑÕ»µØÖ·¡£Èç¹ûstack_baseÊÇ¿ÕÔòthr_create()°´ ÕÕstack_sizeΪÐÂÏ̷߳ÖÅäÒ»¸ö¶ÑÕ»¡£ Stack_size--ÐÂÏ̶߳ÑÕ»µÄ×Ö½ÚÊý¡£Èç¹û±¾ÏîΪ0£¬½«Ê¹ÓÃȱʡֵ£¬Ò»°ã Çé¿öÏÂ×îºÃ½«´ËÏîÉèΪ0¡£ ²¢²»ÊÇÿ¸öÏ̶߳¼ÐèÒªÖ¸¶¨¶ÑÕ»¿Õ¼ä¡£Ï߳̿âΪÿ¸öÏ̵߳ĶÑÕ»·ÖÅä1M µÄÐéÄâÄڴ棬²»±£Áô½»»»¿Õ¼ä¡££¨Ï߳̿âÓÃmmap£¨2£©µÄMAP_NORESERVEµÄÑ¡Ïî À´ÊµÏÖÕâÖÖ·ÖÅ䣩¡£ Start_routine--Ö¸¶¨Ï߳̿ªÊ¼Ö´Ðеĺ¯Êý¡£Èç¹ûstart_routine·µ»Ø£¬ Ï߳̽«Óøú¯ÊýµÄ·µ»ØÖµ×÷ΪÍ˳ö״̬¶øÍ˳ö¡££¨²Î¿¼thr_exit(3T)£©¡£ Flags--Ö¸¶¨ÐÂÏ̵߳ÄÊôÐÔ£¬Ò»°ãÉèÖÃΪ0¡£ FlagsµÄÖµÊÇͨ¹ýÏÂÁÐÄÚÈݵÄλͬ»òÀ´ÊµÏֵģ¨×îºóËĸöflagsÔڸ߼¶ÌØÐÔÖÐ ¸ø³ö£©¡£ 1£® THR_DETACHED ½«ÐÂÏ̷߳ÖÀ룬ʹµÃËüµÄÏ̺߳źÍÆäËû×ÊÔ´ÔÚÏß³Ì ½áÊøʱ¼´¿ÉÒÔ»ØÊÕÀûÓᣵ±Äã²»ÏëµÈ´ýÏß³ÌÖÕֹʱ£¬½«ÆäÖÃλ¡£Èç¹ûûÓÐÃ÷È·µÄ ͬ²½ÐèÇó×è°­£¬Ò»¸ö²»¹ÒÆðµÄ£¬·ÖÀëµÄÏ߳̿ÉÒÔÔÚ´´½¨ÕßµÄthr_create·µ»Ø֮ǰ ÖÕÖ¹²¢½«ÆäÏ̺߳ŷÖÅä¸øÒ»¸öÐĵÃÏ̡߳£ 2£® THR_SUSPENDED¹ÒÆðÐÂỊ̈߳¬Ö±µ½±»thr_continue»½ÐÑ¡£ 3£® THR_BOUND°ÑÐÂÏß³ÌÓÀ¾Ã°ó¶¨ÔÚÒ»¸öLWPÉÏ£¨Éú³ÉÒ»¸ö°ó¶¨Ị̈߳©¡£ 4£® THR_NEW_LWP½«·Ç°ó¶¨Ï̵߳ÄͬʱÐÔ¼¶±ð¼Ó1¡£ 5£® THR_DAEMONÐÂÏß³ÌΪһ¸öÊØ»¤Ï̡߳£ New_thread--Ö¸Ïò´æ´¢ÐÂÏß³ÌIDµÄµØÖ·¡£¶àÊýÇé¿öÏÂÉèÖÃΪ0¡£ Return Values--thr_create()Ôڳɹ¦Ö´Ðк󷵻Ø0²¢Í˳ö¡£ÈκÎÆäËû·µ»ØÖµ ±íÃ÷ÓдíÎó·¢Éú¡£µ±ÒÔÏÂÇé¿ö±»¼ì²âµ½Ê±£¬thr_create()ʧ°Ü²¢·µ»ØÏìÓ¦µÄÖµ¡£ EAGAIN £º³¬³öÁËϵͳÏÞÖÆ£¬ÀýÈç´´½¨ÁËÌ«¶àµÄLWP¡£ ENOMEM£º¿ÉÓÃÄÚ´æ²»¹»´´½¨ÐÂÏ̡߳£ EINVAL£ºstack_base²»ÊÇNULL¶øÇÒstack_size±Èthr_minstack()º¯Êý·µ»ØµÄ ×îС¶ÑջҪС¡£ 2.1.2»ñÈ¡Ï̺߳Šthr_self(3T) »ñµÃ×ÔÉíµÄÏ̺߳š£ #include thread_t thr_self(void) ·µ»ØÖµ--µ÷ÓÃÕßµÄÏ̺߳š£ 2.1.3·ÅÆúÖ´ÐÐ thr_yield(3T) thr_yieldÍ£Ö¹Ö´Ðе±Ç°Ị̈߳¬½«Ö´ÐÐȨÏÞÈøøÓÐÏàͬ»ò¸ü¸ßÓÅÏÈȨµÄÏ̡߳£ #include void thr_yield(void); 2.1.4¹ÒÆð»ò¼ÌÐøÖ´ÐÐÏß³Ì thr_suspend(3T) ¹ÒÆðÏ̡߳£ #include int thr_suspend(thread_t target_thread); thr_suspend()Á¢¼´¹ÒÆðÓÉtarget_threadÖ¸¶¨µÄÏ̡߳£ÔÚthr_suspend³É¹¦ ·µ»Øºó£¬¹ÒÆðµÄÏ̲߳»ÔÙÖ´ÐС£ºó¼ÌµÄthr_suspendÎÞЧ¡£ Return Values--Ö´Ðгɹ¦ºó·µ»Ø0¡£ÆäËû·µ»ØÖµÒâζ×Å´íÎó¡£ÒÔÏÂÇé¿ö·¢Éú ʱ£¬thr_suspend()ʧ°Ü²¢·µ»ØÏà¹ØÖµ¡£ ESRCH: ÔÚµ±Ç°½ø³ÌÖÐÕÒ²»µ½target_thread¡£ Thr_continue(3T) Thr_continue()»Ö¸´Ö´ÐÐÒ»¸ö¹ÒÆðµÄÏ̡߳£Ò»µ©Ïß³ÌÍÑÀë¹ÒÆð״̬£¬ºó¼ÌµÄ thr_continue½«ÎÞЧ¡£ #include int thr_continue(thread_t target_thread); Ò»¸ö¹ÒÆðµÄÏ̲߳»»á±»ÐźŻ½ÐÑ¡£Ðźű»¹ÒÆðÖªµÀÏ̱߳»thr-continue»Ö¸´ Ö´ÐС£ ·µ»ØÖµ--³É¹¦Ö´Ðк󷵻Ø0¡£ÆäËûÖµÒâζ×Å´íÎó¡£ÔÚÒÔÏÂÇé¿ö·¢Éúʱ£¬º¯Êýʧ °Ü²¢·µ»ØÏà¹ØÖµ¡£ ESRCH£ºtarget_threadÔÚµ±Ç°½ø³ÌÖÐÕÒ²»µ½¡£ 2.1.5ÏòÏ̷߳¢ÐźŠthr_kill(3T)ÏòÏ̷߳¢ÐźŠ#include #include int thr_kill(thread_t target_thread,int sig); thr_killÏòÏ̺߳ÅΪtarget_threadµÄÏ̷߳¢ËÍÐźÅsig¡£Target_threadÒ»¶¨ ÒªÓëµ÷ÓÃÏ̴߳¦ÓÚͬһ¸ö½ø³ÌÄÚ¡£²ÎÊýsigÒ»¶¨ÊÇsignal(5)Öж¨Òå¹ýµÄ¡£ µ±sigÊÇ0ʱ£¬´íÎó¼ì²é½«±»Ö´ÐУ¬Ã»ÓÐʵ¼ÊµÄÐźű»·¢ËÍ¡£Õâ¿ÉÒÔÓÃÀ´¼ì²â target_thread²ÎÊýÊÇ·ñºÏ·¨¡£ ·µ»ØÖµ--³É¹¦Ö´Ðк󷵻Ø0£¬ÆäËûÖµÒâζ×Å´íÎó¡£ÔÚÒÔÏÂÇé¿ö·¢Éúʱ£¬º¯Êýʧ °Ü²¢·µ»ØÏà¹ØÖµ¡£ EINVAL£ºsig·Ç·¨£» ESRCH£ºtarget_threadÕÒ²»µ½£» 2.1.6ÉèÖñ¾Ï̵߳ÄÐźÅÑÚÄ£ thr_sigsetmask(3T) »ñÈ¡»ò¸Ä±ä±¾Ï̵߳ÄÐźÅÑÚÄ££¨signal mask£© #include #include int thr_sigsetmask(int how,const sigset_t *set,sigset_t *oset); how²ÎÊý¾ö¶¨ÐźÅÉèÖý«±»ÈçºÎ¸Ä±ä£¬¿ÉÒÔÊÇÏÂÁÐÖµÖ®Ò»£º SIG_BLOCK--ÔÚµ±Ç°ÐźÅÑÚÄ£ÉÏÔö¼Óset£¬setÖ¸Òª×èÈûµÄÐźÅ×é¡£ SIG_UNBLOCK--ÔÚµ±Ç°ÐźÅÑÚÄ£ÉÏÈ¥µôset£¬setÖ¸Òª½â³ý×èÈûµÄÐźÅ×é¡£ SIG_SETMASK--ÓÃеÄÑÚÄ£´úÌæÏÖÓÐÑÚÄ££¬setָеÄÐźÅÑÚÄ£¡£ 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thr_join()º¯Êý×èÈû×ÔÉíËùÔÚµÄỊ̈߳¬Ö±µ½ÓÉwait_forÖ¸¶¨µÄÏß³ÌÖÕÖ¹¡£Ö¸ ¶¨µÄÏß³ÌÒ»¶¨Óë±¾Ïß³ÌÔÚͬһ¸ö½ø³ÌÄÚ²¿£¬¶øÇÒÒ»¶¨²»ÊÇ·ÖÀëÏ̡߳£µ±wait_for ²ÎÊýΪ0ʱ£¬thr_joinµÈ´ýÈκÎÒ»¸ö·Ç·ÖÀëÏ߳̽áÊø¡£»»¾ä»°Ëµ£¬µ±²»Ö¸¶¨Ïß³Ì ºÅʱ£¬ÈκηǷÖÀëÏ̵߳ÄÍ˳ö½«µ¼ÖÂthr_join()·µ»Ø¡£ µ±departed²ÎÊý²»ÊÇNULLʱ£¬ÔÚthr_joinÕý³£·µ»ØʱËüÖ¸Ïò´æ·ÅÖÕÖ¹Ïß³ÌID µÄµØÖ·¡£µ±status²ÎÊý²»ÊÇNULLʱ£¬ÔÚthr_joinÕý³£·µ»ØʱËüÖ¸Ïò´æ·ÅÖÕÖ¹Ïß³Ì Í˳öÂëµÄµØÖ·¡£ Èç¹ûÏ̴߳´½¨Ê±Ö¸¶¨Á˶ÑÕ»£¬ÔÚthr_join·µ»Øʱ¶ÑÕ»¿ÉÒÔ±»»ØÊÕ¡£ÓÉËü·µ»Ø µÄÏ̺߳ſÉÒÔ±»ÖØзÖÅä¡£ ²»ÄÜÓÐÁ½¸öÏß³ÌͬʱµÈ´ýͬһ¸öỊ̈߳¬Èç¹û³öÏÖÕâÖÖÇé¿ö£¬ÆäÖÐÒ»¸öÏß³ÌÕý ³£·µ»Ø£¬ÁíÍâÒ»¸ö·µ»ØESRCH´íÎó¡£ ·µ»ØÖµ--thr_join()ÔÚÕý³£Ö´Ðк󷵻Ø0£¬ÆäËûÖµÒâζ×Å´íÎó¡£ÔÚÒÔÏÂÇé¿ö ·¢Éúʱ£¬º¯Êýʧ°Ü²¢·µ»ØÏà¹ØÖµ¡£ ESRCH wait_for²»ºÏ·¨£¬µÈ´ýµÄÏß³ÌΪ·ÖÀëÏֳɡ£ EDEADLK µÈ´ý×ÔÉí½áÊø¡£ ×îºó²½Öè thr_join()ÓÐÈý¸ö²ÎÊý£¬ÌṩÁËÒ»¶¨µÄÁé»îÐÔ¡£µ±ÄãÐèÒªÒ»¸öÏ̵߳ȴý Ö±µ½ÁíÍâÒ»¸öÖ¸¶¨µÄÏ߳̽áÊø£¬Ó¦µ±°ÑºóÕßµÄIDÌṩΪµÚÒ»²ÎÊý¡£Èç¹û ÐèÒªµÈ´ýµ½ÈκÎÆäËûµÄÏ߳̽áÊø£¬½«µÚÒ»²ÎÊýÖÃÁã¡£ Èç¹ûµ÷ÓÃÕßÏëÖªµÀÊÇÄǸöÏß³ÌÖÕÖ¹£¬µÚ¶þ²ÎÊýÓ¦µ±ÊÇ´¢´æËÀÏ̵߳ÄIDµÄµØÖ·¡£ 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Thr_create(0,0,fetch,&result,0,&helper); /* do something else for a while */ Thr_join(helper,0,&status); /* it's now safe to use result*/ } void fetch(int * result){ /*fetch value from a database */ *result=value; thr_exit(0); } 2.1.10ά»¤Ïß³ÌרÓÐÊý¾Ý µ¥Ïß³ÌC³ÌÐòÓÐÁ½ÖÖ»ù±¾Êý¾Ý--±¾µØÊý¾ÝºÍÈ«¾ÖÊý¾Ý¡£¶àÏß³ÌC³ÌÐòÔö¼ÓÁË Ò»¸öÌØÊâÀàÐÍ--Ïß³ÌרÓÐÊý¾Ý£¨TSD£©¡£·Ç³£ÀàËÆÓëÈ«¾ÖÊý¾Ý£¬Ö»²»¹ýËüÊÇÏß³Ì Ë½Óеġ£ TSDÊÇÒÔÏß³ÌΪ½çÏ޵ġ£TSDÊǶ¨ÒåÏß³Ì˽ÓÐÊý¾ÝµÄΨһ·½·¨¡£Ã¿¸öÏß³ÌרÓÐ Êý¾ÝÏÓÉÒ»¸ö½ø³ÌÄÚΨһµÄ¹Ø¼ü×Ö£¨KEY£©À´±êʶ¡£ÓÃÕâ¸ö¹Ø¼ü×Ö£¬Ï߳̿ÉÒÔ À´´æÈ¡Ïß³Ì˽ÓеÄÊý¾Ý¡£ ά»¤TSDµÄ·½·¨Í¨¹ýÒÔÏÂÈý¸öº¯Êý½øÐУº ¡¤ thr_keycreate()--´´½¨¹Ø¼ü×Ö ¡¤ thr_setspecific()--½«Ò»¸öḬ̈߳ó¶¨ÔÚÒ»¸ö¹Ø¼ü×ÖÉÏ ¡¤ thr_getspecific()--´æ´¢Ö¸¶¨µØÖ·µÄÖµ 2.1.10.1 thr_keycreate(3T) thr_keycreate()ÔÚ½ø³ÌÄÚ²¿·ÖÅäÒ»¸ö±êʶTSDµÄ¹Ø¼ü×Ö¡£¹Ø¼ü×ÖÊǽø³ÌÄÚ ²¿Î¨Ò»µÄ£¬ËùÓÐÏß³ÌÔÚ´´½¨Ê±µÄ¹Ø¼ü×ÖÖµÊÇNULL¡£ Ò»µ©¹Ø¼ü×Ö±»½¨Á¢£¬Ã¿Ò»¸öÏ߳̿ÉÒÔΪ¹Ø¼ü×Ö°ó¶¨Ò»¸öÖµ¡£Õâ¸öÖµ¶ÔÓÚ°ó ¶¨µÄÏß³ÌÀ´ËµÊÇΨһµÄ£¬±»Ã¿¸öÏ̶߳ÀÁ¢Î¬»¤¡£ #include int thr_keycreate(thread_key_t keyp, void (*destructor)(void *value); Èç¹ûthr_keycreate()³É¹¦·µ»Ø£¬·ÖÅäµÄ¹Ø¼ü×Ö±»´æ´¢ÔÚÓÉkeypÖ¸ÏòµÄÇø ÓòÀï¡£µ÷ÓÃÕßÒ»¶¨Òª±£Ö¤´æ´¢ºÍ¶Ô¹Ø¼ü×ֵķÃÎʱ»ÕýÈ·µØͬ²½¡£ Ò»¸ö¿ÉÑ¡µÄÎö¹¹º¯Êý£¬destructor£¬¿ÉÒÔºÍÿ¸ö¹Ø¼ü×ÖÁªÏµÆðÀ´¡£Èç¹ûÒ» ¸ö¹Ø¼ü×ÖµÄdestructor²»¿Õ¶øÇÒÏ̸߳ø¸Ã¹Ø¼ü×ÖÒ»¸ö·Ç¿ÕÖµ£¬ÔÚÏß³ÌÍ˳öʱ¸Ã Îö¹¹º¯Êý±»µ÷Óã¬Ê¹Óõ±Ç°µÄ°ó¶¨Öµ¡£¶ÔÓÚËùÓйؼü×ÖµÄÎö¹¹º¯ÊýÖ´ÐеÄ˳Ðò ÊDz»ÄÜÖ¸¶¨µÄ¡£ ·µ»ØÖµ--thr_keycreate()ÔÚÕý³£Ö´Ðк󷵻Ø0£¬ÆäËûÖµÒâζ×Å´íÎó¡£ÔÚÒÔ ÏÂÇé¿ö·¢Éúʱ£¬º¯Êýʧ°Ü²¢·µ»ØÏà¹ØÖµ¡£ EAGAIN ¹Ø¼ü×ÖµÄÃû×Ö¿Õ¼äÓþ¡ ENOMEM ÄÚ´æ²»¹» 2.1.10.2 Thr_setspecific(3T) #include int thr_setspecific(thread_key_t key,void *value); thr_setspecific()ΪÓÉkeyÖ¸¶¨µÄTSD¹Ø¼ü×Ö°ó¶¨Ò»¸öÓë±¾Ïß³ÌÏà¹ØµÄÖµ¡£ ·µ»ØÖµ--thr_setspecificÔÚÕý³£Ö´Ðк󷵻Ø0£¬ÆäËûÖµÒâζ×Å´íÎó¡£ÔÚÒÔ ÏÂÇé¿ö·¢Éúʱ£¬º¯Êýʧ°Ü²¢·µ»ØÏà¹ØÖµ¡£ ENOMEM ÄÚ´æ²»¹» EINVAL ¹Ø¼ü×Ö·Ç·¨ 2.1.10.3 Thr_getspecific(3T) #include int thr_getspecific(thread_key_t key,void **valuep); thr_getspecific()½«Óëµ÷ÓÃÏß³ÌÏà¹ØµÄ¹Ø¼ü×ÖµÄÖµ´æÈëÓÉvaluepÖ¸¶¨µÄÇø Óò¡£ ·µ»ØÖµ--thr_getspecific()ÔÚÕý³£Ö´Ðк󷵻Ø0£¬ÆäËûÖµÒâζ×Å´íÎó¡£ÔÚ ÒÔÏÂÇé¿ö·¢Éúʱ£¬º¯Êýʧ°Ü²¢·µ»ØÏà¹ØÖµ¡£ EINVAL ¹Ø¼ü×Ö·Ç·¨¡£ 2.1.10.5 È«¾ÖºÍ˽ÓеÄÏß³ÌרÓÐÊý¾Ý Àý³Ì2-2ÊÇ´ÓÒ»¸ö¶àÏ̳߳ÌÐòÖÐժ¼³öÀ´µÄ¡£Õâ¶Î´úÂë¿ÉÒÔ±»ÈÎÒâÊýÁ¿µÄÏß ³ÌÖ´ÐУ¬µ«Ò»¶¨Òª²Î¿¼Á½¸öÈ«¾Ö±äÁ¿£ºerrnoºÍmywindow£¬ÕâÁ½¸öÖµÊÇÒòÏ̶߳ø ÒìµÄ£¬¾ÍÊÇ˵ÊÇÏß³Ì˽Óеġ£ Code Example 2-2 Ïß³ÌרÓÐÊý¾Ý--È«¾ÖÇÒ˽ÓÐµÄ Body(){ ¡­¡­ while(srite(fd,buffer,size)==-1){ if(errno!=EINTR){ fprintf(mywindow,"%s\n",strerror(errno)); exit(1); } } ¡­¡­¡­ } ±¾Ï̵߳Äϵͳ´íÎó´úÂëerrno¿ÉÒÔͨ¹ýÏ̵߳Äϵͳµ÷ÓÃÀ´»ñµÃ£¬¶ø²»ÊÇͨ¹ý ÆäËûÏ̡߳£ËùÒÔÒ»¸öÏ̻߳ñµÃµÄ´íÎóÂëÓëÆäËûÏß³ÌÊDz»Í¬µÄ¡£ ±äÁ¿mywindowÖ¸ÏòÒ»¸öÏß³Ì˽ÓеÄÊäÈëÊä³öÁ÷¡£ËùÒÔ£¬Ò»¸öÏ̵߳Ämywindow ºÍÁíÍâÒ»¸öÏß³ÌÊDz»Í¬µÄ£¬Òò¶ø×îÖÕÌåÏÖÔÚ²»Í¬µÄ´°¿ÚÀΨһµÄÇø±ðÔÚÓÚÏß³Ì ¿âÀ´´¦Àíerrno£¬¶ø³ÌÐòÔ±ÐèÒª¾«ÐÄÉè¼Æmywindow¡£ ÏÂÃæÒ»¸öÀý×Ó˵Ã÷ÁËmywindowµÄÉè¼Æ·½·¨¡£´¦ÀíÆ÷°ÑmywindowµÄÖ¸Õëת»» ³ÉΪ¶Ô_mywindow¹ý³ÌµÄµ÷ÓᣠȻºóµ÷ÓÃthr_getspecific()£¬°ÑÈ«³Ì±äÁ¿mywindow_keyºÍ±êʶÏ̴߳°¿ÚµÄ Êä³ö²ÎÊýwin´«µÝ¸øËü¡£ Code Example 2-3 ½«È«¾Ö²Î¿¼×ª»¯ÎªË½Óвο¼ #define mywindow _mywindow() thread_key_t mywindow_key; FILE * _mywindow(void){ FILE *win; Thr_getspecific(mywindow_key,&win); Return(win); } void thread_start(¡­){ ¡­ make_mywindow(); ¡­ } ±äÁ¿mywindow±êʶÁËÒ»Ààÿ¸öÏ̶߳¼ÓÐ˽Óи±±¾µÄ±äÁ¿£»¾ÍÊÇ˵£¬ÕâЩ±äÁ¿ ÊÇÏß³ÌרÓÐÊý¾Ý¡£Ã¿¸öÏ̵߳÷ÓÃmake_mywindow()À´³õʼ»¯×Ô¼ºµÄ´°¿Ú£¬²¢ÇÒÉú ³ÉÒ»¸öÖ¸ÏòËüµÄʵÀýmywindow¡£ Ò»µ©¹ý³Ì±»µ÷Óã¬ÏֳɿÉÒÔ°²È«µØ·ÃÎÊmywindow£¬ÔÚ_mywindowº¯ÊýÖ®ºó£¬Ïß ³Ì¿ÉÒÔ·ÃÎÊËüµÄ˽Óд°¿Ú¡£ËùÒÔ£¬¶ÔmywindowµÄ²Ù×÷¾ÍÏóÊÇÖ±½Ó²Ù×÷Ïß³Ì˽ÓÐ Êý¾ÝÒ»Ñù¡£ Code Example 2-4 ÏÔʾÁËÔõÑùÉèÖà Code Example 2-4 ³õʼ»¯TSD Void make_mywindow(void){ FILE **win; Static int once=0; Static mutex_t lock; Mutex_lock(&lock); If (!once){ Once=1; Thr_keycreate(&mywindow_key,free_key); } mutext_unlock(&lock); win=malloc(sizeof(*win)); create_window(win,¡­); thr_setspecific(mywindow_key,win); } void freekey(void *win){ free(win); } Ê×ÏÈ£¬¸ø¹Ø¼ü×Ömywindow_key¸³Ò»¸öΨһµÄÖµ¡£Õâ¸ö¹Ø¼ü×Ö±»ÓÃÓÚ±êʶ TSD¡£ËùÒÔ£¬µÚÒ»¸öµ÷ÓÃmake_mywindowµÄÏ̵߳÷ÓÃthr_keycreate()£¬Õâ¸öº¯ Êý¸øÆäµÚÒ»¸ö²ÎÊý¸³Ò»¸öΨһµÄÖµ¡£µÚ¶þ¸ö²ÎÊýÊÇÒ»¸öÎö¹¹º¯Êý£¬ÓÃÀ´ÔÚÏß³Ì ÖÕÖ¹ºó½«TSDËùÕ¼µÄ¿Õ¼ä»ØÊÕ¡£ 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thr_create(NULL, 0, dofunc, NULL, 0, &tid); (void)thr_sigsetmask(SIGSETMASK, NULL, &orig_mask); 2.1.12»ñµÃ×îС¶ÑÕ» thr_min_stack(3T) ÓÃthr_min_stack(3T)À´»ñµÃÏ̵߳ĶÑÕ»ÏÂÏÞ #include size_t thr_min_stack(void); thr_min_stack()·µ»ØÖ´ÐÐÒ»¸ö¿ÕÏß³ÌËùÐèÒªµÄ¶ÑÕ»´óС£¨¿ÕÏß³ÌÊÇÒ»¸ö´´ ½¨³öÀ´Ö´ÐÐÒ»¸ö¿Õ¹ý³ÌµÄỊ̈߳©¡£ Èç¹ûÒ»¸öÏß³ÌÖ´ÐеIJ»½ö½öÊÇ¿Õ¹ý³Ì£¬Ó¦µ±¸øËü·ÖÅä±Èthr_min_stack()·µ »ØÖµ¸ü¶àµÄ¿Õ¼ä¡£ Èç¹ûÏ̴߳´½¨Ê±ÓÉÓû§Ö¸¶¨Á˶ÑÕ»£¬Óû§Ó¦µ±Îª¸ÃÏ̱߳£Áô×ã¹»µÄ¿Õ¼ä¡£ÔÚ Ò»¸ö¶¯Ì¬Á¬½ÓµÄ»·¾³ÀȷÇÐÖªµÀÏß³ÌËùÐèÒªµÄ×îС¶ÑÕ»ÊǷdz£À§Äѵġ£ ´ó¶àÊýÇé¿öÏ£¬Óû§²»Ó¦µ±×Ô¼ºÖ¸¶¨¶ÑÕ»¡£Óû§Ö¸¶¨µÄ¶ÑÕ»½ö½öÓÃÀ´Ö§³ÖÄÇ Ð©Ï£Íû¿ØÖÆËüÃǵÄÖ´Ðл·¾³µÄÓ¦ÓóÌÐò¡£ Ò»°ãµÄ£¬Óû§Ó¦µ±ÈÃÏ߳̿âÀ´´¦Àí¶ÑÕ»µÄ·ÖÅä¡£Ï߳̿âÌṩµÄȱʡ¶ÑÕ»×ã¹» ÔËÐÐÈκÎÏ̡߳£ 2.1.13ÉèÖÃÏ̵߳ÄͬʱÐԵȼ¶ 2.1.13.1 thr_getconcurrency(3T) ÓÃthr_getconcurrency()À´»ñµÃÆÚÍûµÄͬʱÐԵȼ¶µÄµ±Ç°Öµ¡£Êµ¼ÊÉÏͬʱ»î ¶¯µÄÏß³ÌÊý¿ÉÄÜ»á±ÈÕâ¸öÊý¶à»òÉÙ¡£ #include int thr_getconcurrency(void) ·µ»ØÖµ--thr_getconcurrency()ΪÆÚÍûµÄͬʱÐԵȼ¶·µ»Øµ±Ç°Öµ¡£ 2.1.13.2 Thr_setconcurrency(3T) ÓÃthr_setconcurrency()ÉèÖÃÆÚÍûµÄͬʱÐԵȼ¶¡£ #include int thr_setconcurrency(new_level) ½ø³ÌÖеķǰó¶¨Ï߳̿ÉÄÜÐèҪͬʱ»î¶¯¡£ÎªÁ˱£Áôϵͳ×ÊÔ´£¬Ïß³ÌϵͳµÄȱ ʡ״̬±£Ö¤ÓÐ×ã¹»µÄ»î¶¯Ïß³ÌÀ´ÔËÐÐÒ»¸ö½ø³Ì£¬·ÀÖ¹½ø³ÌÒòΪȱÉÙͬʱÐÔ¶øËÀËø¡£ ÒòΪÕâÒ²Ðí²»»á´´½¨×îÓÐЧµÄͬʱÐԵȼ¶£¬thr_setconcurrency()ÔÊÐíÓ¦Óà ³ÌÐòÓÃnew_level¸øϵͳһЩÌáʾ£¬À´µÃµ½ÐèÒªµÄͬʱÐԵȼ¶¡£ ʵ¼ÊµÄͬʱ»î¶¯µÄÏß³ÌÊý¿ÉÄܱÈnew_level¶à»òÉÙ¡£ ×¢Ò⣬Èç¹ûûÓÐÓÃthr_setconcurrencyµ÷ÕûÖ´ÐÐ×ÊÔ´£¬Óжà¸ö compute-bound(????)Ï̵߳ÄÓ¦ÓóÌÐò½«²»ÄÜ·ÖÅäËùÓеĿÉÔËÐÐÏ̡߳£ ÄãÒ²¿ÉÒÔͨ¹ýÔÚµ÷ÓÃthr_create()ʱÉèÖÃTHR_NEW_LWP±êÖ¾À´»ñµÃÆÚÍûµÄͬ ʱÐԵȼ¶¡£ ·µ»ØÖµ--thr_setconcurrency()ÔÚÕý³£Ö´Ðк󷵻Ø0£¬ÆäËûÖµÒâζ×Å´íÎó¡£ ÔÚÒÔÏÂÇé¿ö·¢Éúʱ£¬º¯Êýʧ°Ü²¢·µ»ØÏà¹ØÖµ¡£ EAGAIN Ö¸¶¨µÄͬʱÐԵȼ¶³¬³öÁËϵͳ×ÊÔ´µÄÉÏÏÞ¡£ EINVAL new_levelµÄֵΪ¸º¡£ 2.1.14µÃµ½»òÉ趨Ï̵߳ÄÓÅÏȼ¶ Ò»¸ö·Ç°ó¶¨Ïß³ÌÔÚµ÷¶Èʱ£¬ÏµÍ³½ö½ö¿¼Âǽø³ÌÄÚµÄÆäËûÏ̵߳ļòµ¥µÄÓÅÏȼ¶£¬ ²»×öµ÷Õû£¬Ò²²»Éæ¼°Äںˡ£Ï̵߳ÄϵͳÓÅÏȼ¶µÄÐÎʽÊÇΨһµÄ£¬ÔÚ´´½¨½ø³Ìʱ¼Ì ³Ð¶øÀ´¡£ 2.1.14.1 Thr_getprio(3T) ÓÃthr_getprio()À´µÃµ½Ï̵߳±Ç°µÄÓÅÏȼ¶¡£ #include int thr_getprio(thread_t target_thread,int *pri) ÿ¸öÏ̴߳ÓËüµÄ´´½¨ÕßÄÇÀï¼Ì³ÐÓÅÏȼ¶£¬thr_getprio°Ñtarget_threadµ±Ç° 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Ben-Ari (Prentice-Hall, 1982) Mccartney