{"id":207548,"date":"2025-07-08T08:16:28","date_gmt":"2025-07-08T00:16:28","guid":{"rendered":"https:\/\/server.hk\/cnblog\/207548\/"},"modified":"2025-07-08T08:16:28","modified_gmt":"2025-07-08T00:16:28","slug":"%e4%b8%ba%e4%bb%80%e4%b9%88%e6%88%91%e4%bc%9a%e9%81%87%e5%88%b0%e6%ad%bb%e9%94%81%ef%bc%8c%e5%8d%b3%e4%bd%bf%e5%ae%83%e5%8c%85%e5%90%ab%e6%97%a0%e9%99%90%e5%be%aa%e7%8e%af%ef%bc%9f","status":"publish","type":"post","link":"https:\/\/server.hk\/cnblog\/207548\/","title":{"rendered":"\u4e3a\u4ec0\u4e48\u6211\u4f1a\u9047\u5230\u6b7b\u9501\uff0c\u5373\u4f7f\u5b83\u5305\u542b\u65e0\u9650\u5faa\u73af\uff1f"},"content":{"rendered":"

<\/b> <\/p>\n

\u5f53\u524d\u4f4d\u7f6e\uff1a ><\/span> ><\/span> ><\/span> ><\/span> \u4e3a\u4ec0\u4e48\u6211\u4f1a\u9047\u5230\u6b7b\u9501\uff0c\u5373\u4f7f\u5b83\u5305\u542b\u65e0\u9650\u5faa\u73af\uff1f<\/span><\/p>\n

\u6765\u6e90\uff1astackoverflow<\/span>
\n2024-04-23 15:33:31<\/span>
\n<\/i>0\u6d4f\u89c8<\/span>
\n<\/i>\u6536\u85cf<\/span> <\/p>\n

\u4eca\u65e5\u4e0d\u80af\u57cb\u5934\uff0c\u660e\u65e5\u4f55\u4ee5\u62ac\u5934\uff01\u6bcf\u65e5\u4e00\u53e5\u52aa\u529b\u81ea\u5df1\u7684\u8bdd\u54c8\u54c8~\u54c8\u55bd\uff0c\u4eca\u5929\u6211\u5c06\u7ed9\u5927\u5bb6\u5e26\u6765\u4e00\u7bc7\u300a\u4e3a\u4ec0\u4e48\u6211\u4f1a\u9047\u5230\u6b7b\u9501\uff0c\u5373\u4f7f\u5b83\u5305\u542b\u65e0\u9650\u5faa\u73af\uff1f\u300b<\/span>\uff0c\u4e3b\u8981\u5185\u5bb9\u662f\u8bb2\u89e3<\/span>\u7b49\u7b49\uff0c\u611f\u5174\u8da3\u7684\u670b\u53cb\u53ef\u4ee5\u6536\u85cf\u6216\u8005\u6709\u66f4\u597d\u7684\u5efa\u8bae\u5728\u8bc4\u8bba\u63d0\u51fa\uff0c\u6211\u90fd\u4f1a\u8ba4\u771f\u770b\u7684\uff01\u5927\u5bb6\u4e00\u8d77\u8fdb\u6b65\uff0c\u4e00\u8d77\u5b66\u4e60\uff01<\/p>\n

\u95ee\u9898\u5185\u5bb9
\n <\/p>\n

\u6211\u5f00\u59cb\u6446\u5f04 go\uff0c\u5e76\u4e14\u5bf9 go \u4f8b\u7a0b\u7740\u8ff7\u3002\u6211\u73b0\u5728\u7f16\u5199\u4e86\u4e00\u4e2a\u7b80\u5355\u7684\u6d4b\u8bd5\uff0c\u770b\u770b\u6211\u662f\u5426\u53ef\u4ee5\u5728\u8fde\u7eed\u6253\u5370\u53d8\u91cf\u7684\u540c\u65f6\u66f4\u6539\u5b83\u7684\u503c\u3002<\/p>\n

\u6211\u73b0\u5728\u6709\u4ee5\u4e0b\u4ee3\u7801\uff1a<\/p>\n

package main\n\nimport (\n    \"fmt\"\n    \"time\"\n)\n\nfunc change(c chan float64) float64 {\n    time.sleep(2 * time.second)\n    return 2.5\n}\n\nfunc main() {\n\n    s := 1.1\n\n    c := make(chan float64)\n    go change(c)\n    s = <-c\n\n    for {\n        fmt.println(s)\n        time.sleep(100 * time.millisecond)\n    }    \n}<\/pre>\n
\u4e0d\u5e78\u7684\u662f\uff0c\u5b83\u4ee5\u9519\u8bef\u7ed3\u675f\uff1a<\/p>\n
fatal error: all goroutines are asleep - deadlock!\n\ngoroutine 1 [chan receive]:\nmain.main()\n        \/home\/kramer65\/repos\/go\/src\/messing_around\/main.go:19 +0x7d\nexit status 2<\/pre>\n
\u6211\u641c\u7d22\u4e86\u4e00\u4e0b\uff0c\u53d1\u73b0\u5f53 main \u51fd\u6570\u7ed3\u675f\u800c goroutine \u5c1a\u672a\u7ed3\u675f\u65f6\uff0c\u5c31\u4f1a\u53d1\u751f\u8fd9\u79cd\u6b7b\u9501\u3002\u4f46\u7531\u4e8e\u6211\u6709\u4e00\u4e2a\u65e0\u9650\u5faa\u73af\uff0c\u6211\u4e0d\u77e5\u9053\u6211\u7684\u4ee3\u7801\u8fd8\u6709\u4ec0\u4e48\u95ee\u9898\u3002<\/p>\n
\u8fd9\u6bb5\u4ee3\u7801\u6709\u4ec0\u4e48\u95ee\u9898\uff0c\u4ee5\u53ca\u5982\u4f55\u5728\u8fde\u7eed\u6253\u5370\u53d8\u91cf\u7684\u540c\u65f6\u66f4\u6539\u5b83\u7684\u503c\uff1f<\/p>\n
 <\/p>\n
\u89e3\u51b3\u65b9\u6848<\/h2>\n
 <\/p>\n
\u770b\u6765\u60a8\u53ef\u80fd\u5bf9\u901a\u9053\u548c go \u4f8b\u7a0b\u6709\u8bef\u89e3\u3002<\/p>\n
\u884c\uff1a<\/p>\n
go change(c)<\/pre>\n
\u4f3c\u4e4e\u8868\u660e\u51fd\u6570 change<\/code> \u5c06\u5199\u5165 c<\/code>\u3002\u7136\u800c\uff0c\u5b83\u6700\u7ec8\u53ea\u662f\u5728\u4e00\u6bb5\u65f6\u95f4\u540e\u8fd4\u56de\u4e00\u4e2a\u503c\u3002<\/p>\n
\u6b64\u503c (2.5<\/code>) \u4e0d\u4f1a\u5728\u4efb\u4f55\u5730\u65b9\u6536\u5230\u3002\u6b64\u5916\uff0cc<\/code> \u4e0d\u4f1a\u88ab\u5199\u5165\u4efb\u4f55\u5730\u65b9\u3002\u6211\u6000\u7591\u60a8\u6253\u7b97\u5c06 2.5<\/code> \u5199\u5165\u901a\u9053 c<\/code>\u3002\u5176\u8bed\u6cd5\u5982\u4e0b\uff1a<\/p>\n
c<-2.5<\/pre>\n
\u56e0\u6b64\uff0c\u5982\u679c\u60a8\u5c06 change<\/code> \u51fd\u6570\u66f4\u6539\u4e3a\uff1a<\/p>\n
func change(c chan float64) {\n    time.sleep(2 * time.second)\n    c <- 2.5\n}<\/pre>\n
\u60a8\u4e0d\u5e94\u8be5\u518d\u770b\u5230\u50f5\u5c40\u3002\u8bf7\u6ce8\u610f\uff0c\u6211\u4e0d\u518d\u8fd4\u56de float64<\/code>\u3002<\/p>\n
\u6211\u505a\u4e86\u4e00\u4e2a\u6f14\u793a\u6765\u786e\u4fdd\u8fd9\u4e00\u70b9\uff1a<\/p>\n
\u8bc4\u8bba\u66f4\u65b0<\/strong><\/p>\n
1.1<\/code> \u5c06\u59cb\u7ec8\u88ab\u901a\u9053\u7684\u503c\u8986\u76d6\u3002\u4f46\u662f\uff0c\u5982\u679c\u60a8\u60f3\u6253\u5370 s<\/code> \u7684\u521d\u59cb\u503c\uff08\u5982\u8bc4\u8bba\u4e2d\u6240\u8ff0\uff09\uff0c\u5219\u5fc5\u987b\u7a0d\u5fae\u66f4\u6539\u6d41\u7a0b\u5e76\u4f7f\u7528 select<\/code> \u8bed\u53e5\uff1a<\/p>\n
package main\n\nimport (\n    \"fmt\"\n    \"time\"\n)\n\nfunc change(c chan float64) {\n    time.sleep(2 * time.second)\n    c <- 2.5\n}\n\nfunc main() {\n\n    s := 1.1\n\n    c := make(chan float64)\n    go change(c)\n\n    for {\n        select {\n        case s = <-c:\n        default:\n            \/\/ c isn't ready yet\n        }\n        fmt.println(s)\n        time.sleep(100 * time.millisecond)\n    }\n}<\/pre>\n
\u73b0\u5728\u60a8\u6709\u4e86 select<\/code> \u8bed\u53e5\uff0c\u60a8\u4e5f\u53ef\u4ee5\u5c06\u5b83\u4e0e time.ticker<\/code> \u4e00\u8d77\u4f7f\u7528\uff1a<\/p>\n
ticker := time.NewTicker(100 * time.Millisecond)\nfor {\n    select {\n    case s = <-c:\n    case <-ticker.C:\n        fmt.Println(s)\n    default:\n        \/\/ c isn't ready yet\n    }\n}<\/pre>\n
\u4eca\u5929\u5e26\u5927\u5bb6\u4e86\u89e3\u4e86\u7684\u76f8\u5173\u77e5\u8bc6\uff0c\u5e0c\u671b\u5bf9\u4f60\u6709\u6240\u5e2e\u52a9\uff1b\u5173\u4e8eGolang\u7684\u6280\u672f\u77e5\u8bc6\u6211\u4eec\u4f1a\u4e00\u70b9\u70b9\u6df1\u5165\u4ecb\u7ecd\uff0c\u6b22\u8fce\u5927\u5bb6\u5173\u6ce8\u516c\u4f17\u53f7\uff0c\u4e00\u8d77\u5b66\u4e60\u7f16\u7a0b~<\/p>\n","protected":false},"excerpt":{"rendered":"
\u5f53\u524d\u4f4d\u7f6e\uff1a > > ...<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4925],"tags":[],"class_list":["post-207548","post","type-post","status-publish","format-standard","hentry","category-4925"],"_links":{"self":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207548","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/comments?post=207548"}],"version-history":[{"count":0,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/posts\/207548\/revisions"}],"wp:attachment":[{"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/media?parent=207548"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/categories?post=207548"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/server.hk\/cnblog\/wp-json\/wp\/v2\/tags?post=207548"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}