{"id":2339,"date":"2017-11-18T11:14:38","date_gmt":"2017-11-18T03:14:38","guid":{"rendered":"http:\/\/www.xttblog.com\/?p=2339"},"modified":"2017-11-18T11:14:38","modified_gmt":"2017-11-18T03:14:38","slug":"shell-bash-%e8%84%9a%e6%9c%ac-set-u-%e5%91%bd%e4%bb%a4%e7%94%a8%e6%b3%95%e8%af%a6%e8%a7%a3","status":"publish","type":"post","link":"https:\/\/www.xttblog.com\/?p=2339","title":{"rendered":"Shell bash \u811a\u672c set -u \u547d\u4ee4\u7528\u6cd5\u8be6\u89e3"},"content":{"rendered":"<p>\n\tBASH \u811a\u672c\u7684 set \u547d\u4ee4\u6709\u5f88\u591a\u53c2\u6570\uff0c\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\u6709\u4e9b\u5199\u9519\u7684\u5185\u5bb9\uff0c\u53cd\u800c\u88ab\u811a\u672c\u5ffd\u7565\u4e86\u3002set -u \u5c31\u53ef\u4ee5\u8ba9\u811a\u672c\u9047\u5230\u9519\u8bef\u65f6\u505c\u6b62\u6267\u884c\uff0c\u5e76\u6307\u51fa\u9519\u8bef\u7684\u884c\u6570\u4fe1\u606f\u3002\u672c\u6587\u4e3b\u8981\u4ecb\u7ecd&nbsp;set -u \uff08set -o nounset\uff09\u547d\u4ee4\u7684\u76f8\u5173\u7528\u6cd5\u3002\n<\/p>\n<p>\n\t\u6267\u884c\u811a\u672c\u7684\u65f6\u5019\uff0c\u5982\u679c\u9047\u5230\u4e0d\u5b58\u5728\u7684\u53d8\u91cf\uff0cBash \u9ed8\u8ba4\u5ffd\u7565\u5b83\u3002\n<\/p>\n<pre class=\"brush:bash;\">\r\n#!\/usr\/bin\/env bash\r\n\r\necho $a\r\necho bar<\/pre>\n<p>\n\t\u4e0a\u9762\u4ee3\u7801\u4e2d\uff0c$a\u662f\u4e00\u4e2a\u4e0d\u5b58\u5728\u7684\u53d8\u91cf\u3002\u6267\u884c\u7ed3\u679c\u5982\u4e0b\u3002\n<\/p>\n<pre class=\"brush:bash;\">\r\n$ bash script.sh\r\n\r\nbar<\/pre>\n<p>\n\t\u53ef\u4ee5\u770b\u5230\uff0cecho $a\u8f93\u51fa\u4e86\u4e00\u4e2a\u7a7a\u884c\uff0cBash \u5ffd\u7565\u4e86\u4e0d\u5b58\u5728\u7684$a\uff0c\u7136\u540e\u7ee7\u7eed\u6267\u884cecho bar\u3002\u5927\u591a\u6570\u60c5\u51b5\u4e0b\uff0c\u8fd9\u4e0d\u662f\u5f00\u53d1\u8005\u60f3\u8981\u7684\u884c\u4e3a\uff0c\u9047\u5230\u53d8\u91cf\u4e0d\u5b58\u5728\uff0c\u811a\u672c\u5e94\u8be5\u62a5\u9519\uff0c\u800c\u4e0d\u662f\u4e00\u58f0\u4e0d\u54cd\u5730\u5f80\u4e0b\u6267\u884c\u3002\n<\/p>\n<p>\n\tset -u\u5c31\u7528\u6765\u6539\u53d8\u8fd9\u79cd\u884c\u4e3a\u3002\u811a\u672c\u5728\u5934\u90e8\u52a0\u4e0a\u5b83\uff0c\u9047\u5230\u4e0d\u5b58\u5728\u7684\u53d8\u91cf\u5c31\u4f1a\u62a5\u9519\uff0c\u5e76\u505c\u6b62\u6267\u884c\u3002\n<\/p>\n<pre class=\"brush:bash;\">\r\n#!\/usr\/bin\/env bash\r\nset -u\r\n\r\necho $a\r\necho bar<\/pre>\n<p>\n\t\u8fd0\u884c\u7ed3\u679c\u5982\u4e0b\u3002\n<\/p>\n<pre class=\"brush:bash;\">\r\n$ bash script.sh\r\nbash: script.sh:\u884c4: a: \u672a\u7ed1\u5b9a\u7684\u53d8\u91cf<\/pre>\n<p>\n\t\u53ef\u4ee5\u770b\u5230\uff0c\u811a\u672c\u62a5\u9519\u4e86\uff0c\u5e76\u4e14\u4e0d\u518d\u6267\u884c\u540e\u9762\u7684\u8bed\u53e5\u3002\n<\/p>\n<p>\n\t-u\u8fd8\u6709\u53e6\u4e00\u79cd\u5199\u6cd5-o nounset\uff0c\u4e24\u8005\u662f\u7b49\u4ef7\u7684\u3002\n<\/p>\n<pre class=\"brush:bash;\">\r\nset -o nounset<\/pre>\n<p>\n\t\u4ee5\u4e0a\u5c31\u662f shell \u811a\u672c set -u \u7684\u4f5c\u7528\u3002<\/p>\n<!-- <audio autoplay=\"autoplay\" height=\"100\" width=\"100\" hidden=\"true\"><source src=\"https:\/\/c.coka.la\/orAvPR.mp3\" type=\"audio\/mp3\"\/><\/audio><img decoding=\"async\" src=\"https:\/\/images.weserv.nl\/?url=https:\/\/ws3.sinaimg.cn\/large\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/> --><p><!-- <img decoding=\"async\" src=\"https:\/\/raw.githubusercontent.com\/xmt1139057136\/xttblog\/master\/8fa5dcfcgy1g4em3rzar5j20ib089ae0.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/>--><img decoding=\"async\" src=\"https:\/\/saas.51autoparts.cn\/api\/admin\/sys-file\/oss\/file?fileName=84db51f8561e448f9a4fda2eff0811f9.jpg\" alt=\"\u4e1a\u4f59\u8349\u516c\u4f17\u53f7\"\/><\/p><p>\u6700\u540e\uff0c\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u4e2a\u4eba\u5fae\u4fe1\u516c\u4f17\u53f7\uff1a\u4e1a\u4f59\u8349\uff08yyucao\uff09\uff01<b>\u53ef\u52a0\u4f5c\u8005\u5fae\u4fe1\u53f7\uff1a<font color=\"red\">xttblog2<\/font>\u3002\u5907\u6ce8\uff1a\u201c1\u201d\uff0c\u6dfb\u52a0\u535a\u4e3b\u5fae\u4fe1\u62c9\u4f60\u8fdb\u5fae\u4fe1\u7fa4\u3002\u5907\u6ce8\u9519\u8bef\u4e0d\u4f1a\u540c\u610f\u597d\u53cb\u7533\u8bf7\u3002<\/b>\u518d\u6b21\u611f\u8c22\u60a8\u7684\u5173\u6ce8\uff01\u540e\u7eed\u6709\u7cbe\u5f69\u5185\u5bb9\u4f1a\u7b2c\u4e00\u65f6\u95f4\u53d1\u7ed9\u60a8\uff01\u539f\u521b\u6587\u7ae0\u6295\u7a3f\u8bf7\u53d1\u9001\u81f3532009913@qq.com\u90ae\u7bb1\u3002\u5546\u52a1\u5408\u4f5c\u4e5f\u53ef\u6dfb\u52a0\u4f5c\u8005\u5fae\u4fe1\u8fdb\u884c\u8054\u7cfb\uff01<\/p><p>\u672c\u6587\u539f\u6587\u51fa\u5904\uff1a<a href=\"https:\/\/www.xttblog.com\">\u4e1a\u4f59\u8349<\/a>\uff1a &raquo; <a href=\"https:\/\/www.xttblog.com\/?p=2339\">Shell bash \u811a\u672c set -u \u547d\u4ee4\u7528\u6cd5\u8be6\u89e3<\/a><\/p><!-- <div class=\"bd-reward-stl\"><button id=\"bdRewardBtn\"><span><\/span><\/button><\/div> -->","protected":false},"excerpt":{"rendered":"<p>BASH \u811a\u672c\u7684 set \u547d\u4ee4\u6709\u5f88\u591a\u53c2\u6570\uff0c\u5728\u5b9e\u9645\u5e94\u7528\u4e2d\u6709\u4e9b\u5199\u9519\u7684\u5185\u5bb9\uff0c\u53cd\u800c\u88ab\u811a\u672c\u5ffd\u7565\u4e86\u3002set -u \u5c31\u53ef\u4ee5\u8ba9 [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[118,6],"tags":[706,1130],"class_list":["post-2339","post","type-post","status-publish","format-standard","hentry","category-ndisdevelop","category-yyzt","tag-linux","tag-shell-"],"_links":{"self":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2339","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2339"}],"version-history":[{"count":1,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2339\/revisions"}],"predecessor-version":[{"id":2340,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=\/wp\/v2\/posts\/2339\/revisions\/2340"}],"wp:attachment":[{"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2339"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2339"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.xttblog.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2339"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}