<\/p>\n\/*function of p opration*\/
void P(int semid,int index)
{
struct sembuf sem;
\tsem.sem_num = index;
\tsem.sem_op = -1;
\t\/\/mark of option\uff1a0 or IPC_NOWAIT and so on
\tsem.sem_flg = 0;
\t\/\/the ‘1’ in this sentence means the number of commands
\tsemop(semid,&sem,1);\t\t
\treturn;
}<\/p>\n
\/*function of v opration*\/
void V(int semid,int index)
{
struct sembuf sem;
\tsem.sem_num = index;
\tsem.sem_op = 1;
\tsem.sem_flg = 0;
\tsemop(semid,&sem,1);
\treturn;
}<\/p>\n
int semid;
pthread_t p1,p2;
int sharedInt=0;
void *subp1();
void *subp2();<\/p>\n
\/*in Linux,the return of the function main must be int,cann’t be void*\/
int main()
{
union semun semopts;
\tint res;
\t\/*\u8bf7\u6c42\u4e24\u4e2a\u4fe1\u53f7\u91cf*\/
\tsemid = semget(300,2,IPC_CREAT|0666);
\tif (semid<0) {
\t\tprintf(“error”);
\t return;
\t}
\t\/*\u521d\u59cb\u5316\u7b2c\u4e00\u4e2a\u4fe1\u53f7\u91cf\u7684\u503c\u4e3a1*\/
\tsemopts.val = 1;
\tres=semctl(semid,0,SETVAL,semopts);
\t\/*\u521d\u59cb\u5316\u7b2c\u4e8c\u4e2a\u4fe1\u53f7\u91cf\u7684\u503c\u4e3a0*\/
\tsemopts.val = 0;
\tres=semctl(semid,1,SETVAL,semopts);
\tif (res < 0) return;
\t\/*\u521b\u5efa\u4e24\u4e2a\u7ebf\u7a0b*\/
\tpthread_create(&p2,NULL,subp2,NULL);
pthread_create(&p1,NULL,subp1,NULL);
\t\/*\u7b49\u5f85\u4e24\u4e2a\u7ebf\u7a0b\u7ed3\u675f*\/
\tpthread_join(p1,NULL);
\tpthread_join(p2,NULL);
\tsemctl(semid,0,IPC_RMID,0);
}<\/p>\n
\/*produce number*\/
void *subp1()
{
\tint i,j;
\tfor (i=0; i<10;i++) {
sleep(i+1);
\t printf(“\\nready to produce!\\n”);
\t\tP(semid,0);
\t\tsharedInt++;
\t\tprintf(“have produced %d!\\n”,sharedInt);
\t\tV(semid,1);
\t}
\treturn;
}<\/p>\n
\/*get number*\/
void *subp2()
{
\tint i,j;
\tfor (i=0;i<10;i++) {
sleep(10-i);
\t printf(“\\nready to get!\\n”);
\t\tP(semid,1);
printf(“have got %d!\\n”,sharedInt);
\t\tV(semid,0);
\t}
\treturn;
}<\/p>\n<\/blockquote>\n","protected":false},"excerpt":{"rendered":"
\u64cd\u4f5c\u7cfb\u7edf\u5b9e\u9a8c\u7528\u7684\u7a0b\u5e8f\uff0c\u4fdd\u7559\u4e00\u4e2a\u3002\u6ca1\u4ec0\u4e48\u6280\u672f\u542b\u91cf\uff0c\u8bf7\u89c1\u8c05^_^ \u8fd9\u4e2a\u7a0b\u5e8f\u5c31\u662f\u89e3\u51b3\u90a3\u4e2a\u8457\u540d\u7684\u201c\u751f\u4ea7\u8005\u2014\u6d88\u8d39\u8005\u201d\u7684\u95ee\u9898\uff0c\u8c8c\u4f3c\u7ebf\u7a0b\u7684\u540c\u6b65\u90fd\u8bb2\u8fd9\u4e2a\u95ee\u9898\uff0cJava\u91cc\u9762\u4e5f\u6709\uff0c\u4e0d\u8fc7\u64cd\u4f5c\u8d77\u6765\u8c8c\u4f3c\u8981\u66f4\u7b80\u5355\u4e00\u70b9\u3002 \u5728\u8fd9\u4e2a\u7a0b\u5e8f\u91ccsubp1()\u7528\u6765\u751f\u4ea7\u4e00\u4e2a int \u6570\u636e\uff0csubp2()\u7528\u6765\u83b7\u53d6\u8fd9\u4e2a\u6574\u6570\u3002\u9996\u5148\u662fsubp1()\u751f\u4ea7\u4e00\u4e2a\u6570\u636e\uff0csubp2()\u518d\u53bb\u83b7\u53d6\u8fd9\u4e2a\u6570\u636e\u3002subp2()\u83b7\u53d6\u6570\u636e\u7684\u9996\u8981\u6761\u4ef6\u662f subp1()\u5df2\u7ecf\u751f\u4ea7\u4e86\u4e00\u4e2a\u65b0\u7684\u6570\u636e\uff0csubp1()\u751f\u4ea7\u4e00\u4e2a\u65b0\u6570\u636e\u7684\u524d\u63d0\u662fsubp2()\u5df2\u7ecf\u83b7\u5f97\u4e86subp1()\u751f\u4ea7\u7684\u524d\u4e00\u4e2a\u6570\u636e\u3002[#afdream.com#] \/*thread synchronization*\/\/*thread.c*\/\/*Afdream.com*\/\/*2005-12-20*\/#include #include #include #include #include #include \/*function of p opration*\/void P(int semid,int index){ struct sembuf sem; sem.sem_num = index; sem.sem_op = -1; \/\/mark of option\uff1a0 or IPC_NOWAIT and so on sem.sem_flg = 0; \/\/the ‘1’ in this sentence means the number of commands semop(semid,&sem,1); return;} \/*function of v … <\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[19,26],"class_list":["post-244","post","type-post","status-publish","format-standard","hentry","category-coding","tag-Linux","tag-26"],"views":30336,"_links":{"self":[{"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/posts\/244","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/comments?post=244"}],"version-history":[{"count":0,"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/posts\/244\/revisions"}],"wp:attachment":[{"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/media?parent=244"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/categories?post=244"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/fdream.net\/blog\/wp-json\/wp\/v2\/tags?post=244"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}