{"id":367,"date":"2021-11-24T01:15:02","date_gmt":"2021-11-23T17:15:02","guid":{"rendered":"https:\/\/pixelhn.cn\/?p=367"},"modified":"2021-12-12T22:50:03","modified_gmt":"2021-12-12T14:50:03","slug":"linux-%e6%97%b6%e9%97%b4%ef%bc%881%ef%bc%89","status":"publish","type":"post","link":"https:\/\/pixelhn.cn\/?p=367","title":{"rendered":"Linux\u2014\u2014\u65f6\u95f4\uff081\uff09"},"content":{"rendered":"<h2>Linux\u2014\u2014\u65f6\u95f4\uff081\uff09<\/h2>\n<p>Linux\u4e2d\uff0c\u7528\u4e8e\u4fdd\u5b58\u65f6\u95f4\u503c\u7684\u6570\u636e\u7ed3\u6784\u662f\uff1a<\/p>\n<pre><code class=\"language-c\">struct timeval{\n    long tv_sec;\n    long tv_usec;\n};\n<\/code><\/pre>\n<p>\u5176\u4e2d<code>tv_sec<\/code>\u7684\u5355\u4f4d\u4e3a\u79d2\uff0c<code>tv_usec<\/code>\u7684\u5355\u4f4d\u4e3a\u5fae\u79d2\uff081\u79d2(s) =1000\u6beb\u79d2(ms)\uff0c1\u6beb\u79d2(ms)=1000\u5fae\u79d2 (us)\uff0c\u53731\u79d2(s)=10<sup>6<\/sup>\u5fae\u79d2(us)\uff09,\u4f7f\u7528\u8be5\u6570\u636e\u8868\u53ef\u4ee5\u8868\u793a\u4ece\u67d0\u4e2a\u65f6\u523b\u5230\u53e6\u4e00\u4e2a\u65f6\u523b\uff08\u6bd4\u5982\u5230\u73b0\u5728\uff09\u7ecf\u8fc7\u4e86\u591a\u5c11\u7684\u65f6\u95f4\u3002<\/p>\n<p>\u4f7f\u7528\u7cfb\u7edf\u8c03\u7528<code>gettimeofday()<\/code>\u53ef\u4ee5\u83b7\u53d6\u7531\u5185\u6838\u7ef4\u62a4\u7684\u5f53\u524d\u65f6\u95f4\uff1a\u8be5\u65f6\u95f4\u662f\u4ece<strong>1970\u5e741\u67081\u65e5\uff08\u683c\u6797\u5a01\u6cbb\u65f6\u95f400:00:00\uff09<\/strong>\u5f00\u59cb\u8ba1\u7b97\u5230\u73b0\u5728\u65f6\u523b\u6240\u7ecf\u8fc7\u7684\u65f6\u95f4\u3002<\/p>\n<pre><code class=\"language-c\">gettimeofday(\n    struct  timeval *tv,\n    struct  timezone *tz\n);\n<\/code><\/pre>\n<p>\u572864\u4f4d\u7684Linux\u8ba1\u7b97\u673a\u4e0a\uff0c\u957f\u6574\u578b<code>long<\/code>\u4f7f\u75288\u4e2a\u5b57\u8282\uff0c\u6309\u7167\u4e00\u5e74\u5927\u7ea62<sup>25<\/sup>\u79d2\uff0c\u5373\u4fbf\u662f\u6709\u7b26\u53f7\u957f\u6574\u578b\uff0c\u5927\u7ea6\u53ef\u4ee5\u8868\u793a\u52302<sup>38<\/sup>\u5e74\u4e4b\u540e\uff1b\u800c\u4e00\u4e9b\u8ba1\u7b97\u673a\u4e0a\u957f\u6574\u578b<code>long<\/code>\u4f7f\u75284\u4e2a\u5b57\u8282\uff0c\u5373\u5927\u7ea6\u52302034\u5e74\u65f6\uff0c\u7ef4\u62a4\u7684\u65f6\u95f4\u5c06\u53d1\u751f\u6ea2\u51fa\u3002<\/p>\n<hr \/>\n<p>\u6d4b\u8bd5\u4ee3\u7801\uff1a<\/p>\n<pre><code class=\"language-c\">\/\/getime.c\n#include&lt;stdio.h&gt;\n#include&lt;sys\/time.h&gt;\n\nstruct timeval thetime;\nvoid main(){\n        long minute,hour;\n        int day,year;\n        gettimeofday(&amp;thetime,NULL);\n\n        printf(\"%ld,%ld\\n\",thetime.tv_sec,thetime.tv_usec);\n\n        minute = thetime.tv_sec \/ 60;\n        hour = minute \/ 60;\n        day = hour \/ 24;\n        year = day \/ 365;\n\n        printf(\"size of long:%ld\\n\",sizeof(long));\n        printf(\"min:%ld\\nhour:%ld\\nday:%d\\nyear:%d\\n\\n\",minute,hour,day,year);\n}\n<\/code><\/pre>\n<p>\u8fd0\u884c<\/p>\n<pre><code class=\"language-shell\">$ cc getime.c \n$ .\/a.out \n1637687458,179524\nsize of long:8\nmin:27294790\nhour:454913\nday:18954\nyear:51\n\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"<p>Linux\u2014\u2014\u65f6\u95f4\uff081\uff09 Linux\u4e2d\uff0c\u7528\u4e8e\u4fdd\u5b58\u65f6\u95f4\u503c\u7684\u6570\u636e\u7ed3\u6784\u662f\uff1a struct timeval{ long&hellip; <a class=\"more-link\" href=\"https:\/\/pixelhn.cn\/?p=367\">\u7ee7\u7eed\u9605\u8bfb<span class=\"screen-reader-text\">Linux\u2014\u2014\u65f6\u95f4\uff081\uff09<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"jetpack_post_was_ever_published":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[4,1],"tags":[],"class_list":["post-367","post","type-post","status-publish","format-standard","hentry","category-linux","category-all","entry"],"jetpack_featured_media_url":"","jetpack-related-posts":[],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/pixelhn.cn\/index.php?rest_route=\/wp\/v2\/posts\/367","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/pixelhn.cn\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/pixelhn.cn\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/pixelhn.cn\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/pixelhn.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=367"}],"version-history":[{"count":4,"href":"https:\/\/pixelhn.cn\/index.php?rest_route=\/wp\/v2\/posts\/367\/revisions"}],"predecessor-version":[{"id":390,"href":"https:\/\/pixelhn.cn\/index.php?rest_route=\/wp\/v2\/posts\/367\/revisions\/390"}],"wp:attachment":[{"href":"https:\/\/pixelhn.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=367"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/pixelhn.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=367"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/pixelhn.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=367"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}