{"id":162242,"date":"2019-11-23T10:00:01","date_gmt":"2019-11-23T02:00:01","guid":{"rendered":"https:\/\/lrxjmw.cn\/?p=162242"},"modified":"2019-10-24T09:56:11","modified_gmt":"2019-10-24T01:56:11","slug":"shell-basic-operator","status":"publish","type":"post","link":"https:\/\/lrxjmw.cn\/shell-basic-operator.html","title":{"rendered":"Shell \u57fa\u672c\u8fd0\u7b97\u7b26"},"content":{"rendered":"<table>\n<tbody>\n<tr>\n<td style=\"padding: 5px 12px; width: 25px; font-size: 22px; text-align: center; background: #E8E8E8; line-height: 30px; color: #999;\">\u5bfc\u8bfb<\/td>\n<td style=\"padding: 10px 10px 12px; line-height: 20px;\"><strong>Shell \u548c\u5176\u4ed6\u7f16\u7a0b\u8bed\u8a00\u4e00\u6837\uff0c\u652f\u6301\u591a\u79cd\u8fd0\u7b97\u7b26\u3002\u5305\u62ec\uff1a\u7b97\u6570\u8fd0\u7b97\u7b26\uff0c\u5173\u7cfb\u8fd0\u7b97\u7b26\uff0c\u5e03\u5c14\u8fd0\u7b97\u7b26\uff0c\u5b57\u7b26\u4e32\u8fd0\u7b97\u7b26\uff0c\u6587\u4ef6\u6d4b\u8bd5\u8fd0\u7b97\u7b26\u3002<\/strong><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-162246\" src=\"https:\/\/lrxjmw.cn\/wp-content\/uploads\/2019\/10\/4-7.jpg\" alt=\"\" width=\"456\" height=\"340\" \/><\/p>\n<p>\u539f\u751fbash\u4e0d\u652f\u6301\u7b80\u5355\u7684\u6570\u5b66\u8fd0\u7b97\uff0c\u4f46\u662f\u53ef\u4ee5\u901a\u8fc7\u5176\u4ed6\u547d\u4ee4\u6765\u5b9e\u73b0\uff0c\u4f8b\u5982 awk \u548c expr\uff0cexpr \u6700\u5e38\u7528\u3002<\/p>\n<p>expr \u662f\u4e00\u6b3e\u8868\u8fbe\u5f0f\u8ba1\u7b97\u5de5\u5177\uff0c\u4f7f\u7528\u5b83\u80fd\u5b8c\u6210\u8868\u8fbe\u5f0f\u7684\u6c42\u503c\u64cd\u4f5c\u3002<\/p>\n<p>\u4f8b\u5982\uff0c\u4e24\u4e2a\u6570\u76f8\u52a0(\u6ce8\u610f\u4f7f\u7528\u7684\u662f\u53cd\u5f15\u53f7 ` \u800c\u4e0d\u662f\u5355\u5f15\u53f7 ')\uff1a<\/p>\n<pre>\u5b9e\u4f8b\r\n#!\/bin\/bash\r\n\r\nval=`expr 2 + 2`\r\necho \"\u4e24\u6570\u4e4b\u548c\u4e3a : $val\"<\/pre>\n<p>\u6267\u884c\u811a\u672c\uff0c\u8f93\u51fa\u7ed3\u679c\u5982\u4e0b\u6240\u793a\uff1a<\/p>\n<pre>\u4e24\u6570\u4e4b\u548c\u4e3a : 4<\/pre>\n<p>\u4e24\u70b9\u6ce8\u610f\uff1a<\/p>\n<p>\u8868\u8fbe\u5f0f\u548c\u8fd0\u7b97\u7b26\u4e4b\u95f4\u8981\u6709\u7a7a\u683c\uff0c\u4f8b\u5982 2+2 \u662f\u4e0d\u5bf9\u7684\uff0c\u5fc5\u987b\u5199\u6210 2 + 2\uff0c\u8fd9\u4e0e\u6211\u4eec\u719f\u6089\u7684\u5927\u591a\u6570\u7f16\u7a0b\u8bed\u8a00\u4e0d\u4e00\u6837\u3002<\/p>\n<p>\u5b8c\u6574\u7684\u8868\u8fbe\u5f0f\u8981\u88ab ` ` \u5305\u542b\uff0c\u6ce8\u610f\u8fd9\u4e2a\u5b57\u7b26\u4e0d\u662f\u5e38\u7528\u7684\u5355\u5f15\u53f7\uff0c\u5728 Esc \u952e\u4e0b\u8fb9\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u539f\u751fbash\u4e0d\u652f\u6301\u7b80\u5355\u7684\u6570\u5b66\u8fd0\u7b97\uff0c\u4f46\u662f\u53ef\u4ee5\u901a\u8fc7\u5176\u4ed6\u547d\u4ee4\u6765\u5b9e\u73b0\uff0c\u4f8b\u5982 awk \u548c expr\uff0cexpr \u6700\u5e38\u7528\u3002  [&hellip;]<\/p>\n","protected":false},"author":321,"featured_media":162247,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[55],"tags":[],"class_list":["post-162242","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-thread"],"acf":[],"_links":{"self":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts\/162242","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/users\/321"}],"replies":[{"embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/comments?post=162242"}],"version-history":[{"count":5,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts\/162242\/revisions"}],"predecessor-version":[{"id":162426,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/posts\/162242\/revisions\/162426"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/media\/162247"}],"wp:attachment":[{"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/media?parent=162242"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/categories?post=162242"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/lrxjmw.cn\/wp-json\/wp\/v2\/tags?post=162242"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}