{"id":28,"date":"2016-03-20T14:29:26","date_gmt":"2016-03-20T06:29:26","guid":{"rendered":"https:\/\/wangqf.com\/?p=28"},"modified":"2016-03-20T14:29:26","modified_gmt":"2016-03-20T06:29:26","slug":"shell-%e6%95%b0%e5%ad%a6%e8%bf%90%e7%ae%97","status":"publish","type":"post","link":"https:\/\/wangqf.com\/?p=28","title":{"rendered":"Shell \u6570\u5b66\u8fd0\u7b97"},"content":{"rendered":"
\n

shell\u9ed8\u8ba4\u628a\u53d8\u91cf\u4f5c\u4e3a\u5b57\u7b26\u4e32\u5904\u7406\uff0c\u6570\u5b66\u8fd0\u7b97\u4e0d\u50cf\u5176\u4ed6\u8bed\u8a00\u90a3\u4e48\u7b80\u5355\u3002
\n\u5e38\u89c1\u7684\u5904\u7406\u547d\u4ee4\u6216\u64cd\u4f5c\u7b26\u6709expr, let, bc,[], (())\u3002<\/p>\n

expr<\/h2>\n

expr \u4e0d\u4ec5\u652f\u6301\u52a0\u51cf\u4e58\u9664\u8fd0\u7b97\uff0c\u8fd8\u652f\u6301\u4e0e\u6216\u5927\u4e8e\u5c0f\u4e8e\u7b49\u903b\u8f91\u8fd0\u7b97\u3002<\/p>\n

expr 1 + 2\nvar=`expr 1 + 2`\necho $var\n<\/code><\/pre>\n
\u65b9\u62ec\u53f7<\/h2>\n
\u65b9\u62ec\u53f7\u5199\u8d77\u6765\u8981\u65b9\u4fbf\u5f88\u591a\uff0c\u4f46\u662f\u548cexpr\u76f8\u540c\uff0c\u90fd\u4e0d\u652f\u6301\u6d6e\u70b9\u8fd0\u7b97\u3002<\/p>\n
var=$[1 + 2]\necho $var\nvar2=$[$var + 3]\necho $var2\n<\/code><\/pre>\n
let<\/h2>\n
let\u540e\u9762\u8868\u8fbe\u5f0f\u4e0d\u80fd\u6709\u7a7a\u683c\uff0c\u5982\u679c\u9700\u8981\u53ef\u4ee5\u89c1\u5f15\u53f7\uff0c\u800cexpr\u8fd0\u7b97\u91cf\u548c\u8fd0\u7b97\u7b26\u4e4b\u95f4\u5fc5\u987b\u6709\u7a7a\u683c\u3002<\/p>\n
let var=1+2\nlet var=var+3\nlet \"var = var \/ 2\"\necho $var\n<\/code><\/pre>\n
bc<\/h2>\n
\u5982\u679c\u9700\u8981\u652f\u6301\u6d6e\u70b9\u8fd0\u7b97\uff0c\u53ef\u4ee5\u4f7f\u7528bc\u547d\u4ee4\u3002<\/p>\n
var=`echo 1.5 + 1 | bc`\necho $var\n<\/code><\/pre>\n
\u53c2\u8003\u6587\u732e\uff1a
\n[1] Linux\u547d\u4ee4\u884c\u4e0eShell\u811a\u672c\u7f16\u7a0b\u5927\u5168 \u7b2c2\u7248<\/p>\n","protected":false},"excerpt":{"rendered":"
shell\u9ed8\u8ba4\u628a\u53d8\u91cf\u4f5c\u4e3a\u5b57\u7b26\u4e32\u5904\u7406\uff0c\u6570\u5b66\u8fd0\u7b97\u4e0d\u50cf\u5176\u4ed6\u8bed\u8a00\u90a3\u4e48\u7b80\u5355\u3002 \u5e38\u89c1\u7684\u5904\u7406\u547d\u4ee4\u6216\u64cd\u4f5c\u7b26\u6709expr, let … \u7ee7\u7eed\u9605\u8bfb\u201cShell \u6570\u5b66\u8fd0\u7b97\u201d<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[2],"tags":[],"class_list":["post-28","post","type-post","status-publish","format-standard","hentry","category-2"],"_links":{"self":[{"href":"https:\/\/wangqf.com\/index.php?rest_route=\/wp\/v2\/posts\/28","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wangqf.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wangqf.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wangqf.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/wangqf.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=28"}],"version-history":[{"count":0,"href":"https:\/\/wangqf.com\/index.php?rest_route=\/wp\/v2\/posts\/28\/revisions"}],"wp:attachment":[{"href":"https:\/\/wangqf.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=28"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wangqf.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=28"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wangqf.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=28"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}