{"id":2172,"date":"2017-10-31T14:27:51","date_gmt":"2017-10-31T06:27:51","guid":{"rendered":"http:\/\/www.51cos.com\/?p=2172"},"modified":"2017-10-31T14:27:51","modified_gmt":"2017-10-31T06:27:51","slug":"21%e4%bd%bf%e7%94%a8%e5%92%8clinux%e5%91%bd%e4%bb%a4%e4%b9%8btee","status":"publish","type":"post","link":"http:\/\/www.51cos.com\/?p=2172","title":{"rendered":"2>&1\u4f7f\u7528\u548cLinux\u547d\u4ee4\u4e4btee"},"content":{"rendered":"

shell\u4e2d\u53ef\u80fd\u7ecf\u5e38\u80fd\u770b\u5230\uff1a>\/dev\/null 2>&1 <\/p>\n

\/dev\/null \u4ee3\u8868\u7a7a\u8bbe\u5907\u6587\u4ef6
\n> \u4ee3\u8868\u91cd\u5b9a\u5411\u5230\u54ea\u91cc\uff0c\u4f8b\u5982\uff1aecho “123” > \/home\/123.txt
\n1 \u8868\u793astdout\u6807\u51c6\u8f93\u51fa\uff0c\u7cfb\u7edf\u9ed8\u8ba4\u503c\u662f1\uff0c\u6240\u4ee5”>\/dev\/null”\u7b49\u540c\u4e8e”1>\/dev\/null”
\n2 \u8868\u793astderr\u6807\u51c6\u9519\u8bef
\n& \u8868\u793a\u7b49\u540c\u4e8e\u7684\u610f\u601d\uff0c2>&1\uff0c\u8868\u793a2\u7684\u8f93\u51fa\u91cd\u5b9a\u5411\u7b49\u540c\u4e8e1<\/p>\n

\u90a3\u4e48\u672c\u6587\u6807\u9898\u7684\u8bed\u53e5\uff1a
\n1>\/dev\/null \u9996\u5148\u8868\u793a\u6807\u51c6\u8f93\u51fa\u91cd\u5b9a\u5411\u5230\u7a7a\u8bbe\u5907\u6587\u4ef6\uff0c\u4e5f\u5c31\u662f\u4e0d\u8f93\u51fa\u4efb\u4f55\u4fe1\u606f\u5230\u7ec8\u7aef\uff0c\u8bf4\u767d\u4e86\u5c31\u662f\u4e0d\u663e\u793a\u4efb\u4f55\u4fe1\u606f\u3002
\n2>&1 \u63a5\u7740\uff0c\u6807\u51c6\u9519\u8bef\u8f93\u51fa\u91cd\u5b9a\u5411\u7b49\u540c\u4e8e \u6807\u51c6\u8f93\u51fa\uff0c\u56e0\u4e3a\u4e4b\u524d\u6807\u51c6\u8f93\u51fa\u5df2\u7ecf\u91cd\u5b9a\u5411\u5230\u4e86\u7a7a\u8bbe\u5907\u6587\u4ef6\uff0c\u6240\u4ee5\u6807\u51c6\u9519\u8bef\u8f93\u51fa\u4e5f\u91cd\u5b9a\u5411\u5230\u7a7a\u8bbe\u5907\u6587\u4ef6\u3002<\/p>\n

Shell\u4f1a\u81ea\u52a8\u4e3a\u6211\u4eec\u6253\u5f00\u548c\u5173\u95ed0\u30011\u30012\u8fd9\u4e09\u4e2a\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u6211\u4eec\u4e0d\u9700\u8981\u663e\u5f0f\u5730\u6253\u5f00\u6216\u5173\u95ed\u5b83\u4eec\u3002\u6807\u51c6\u8f93\u5165\u662f\u547d\u4ee4\u7684\u8f93\u5165\uff0c\u9ed8\u8ba4\u6307\u5411\u952e\u76d8\uff1b\u6807\u51c6\u8f93\u51fa\u662f\u547d\u4ee4\u7684\u8f93\u51fa\uff0c\u9ed8\u8ba4\u6307\u5411\u5c4f\u5e55\uff1b\u6807\u51c6\u9519\u8bef\u662f\u547d\u4ee4\u9519\u8bef\u4fe1\u606f\u7684\u8f93\u51fa\uff0c\u9ed8\u8ba4\u6307\u5411\u5c4f\u5e55\u3002<\/p>\n

\u4e00 \u76f8\u5173\u77e5\u8bc6<\/p>\n

1\uff09\u9ed8\u8ba4\u5730\uff0c\u6807\u51c6\u7684\u8f93\u5165\u4e3a\u952e\u76d8\uff0c\u4f46\u662f\u4e5f\u53ef\u4ee5\u6765\u81ea\u6587\u4ef6\u6216\u7ba1\u9053\uff08pipe |\uff09\u3002
\n2\uff09\u9ed8\u8ba4\u5730\uff0c\u6807\u51c6\u7684\u8f93\u51fa\u4e3a\u7ec8\u7aef\uff08terminal)\uff0c\u4f46\u662f\u4e5f\u53ef\u4ee5\u91cd\u5b9a\u5411\u5230\u6587\u4ef6\uff0c\u7ba1\u9053\u6216\u540e\u5f15\u53f7\uff08backquotes `\uff09\u3002
\n3) \u9ed8\u8ba4\u5730\uff0c\u6807\u51c6\u7684\u9519\u8bef\u8f93\u51fa\u5230\u7ec8\u7aef\uff0c\u4f46\u662f\u4e5f\u53ef\u4ee5\u91cd\u5b9a\u5411\u5230\u6587\u4ef6\u3002
\n4\uff09\u6807\u51c6\u7684\u8f93\u5165\uff0c\u8f93\u51fa\u548c\u9519\u8bef\u8f93\u51fa\u5206\u522b\u8868\u793a\u4e3aSTDIN,STDOUT,STDERR\uff0c\u4e5f\u53ef\u4ee5\u75280\uff0c1\uff0c2\u6765\u8868\u793a\u3002
\n5\uff09\u5176\u5b9e\u9664\u4e86\u4ee5\u4e0a\u5e38\u7528\u76843\u4e2d\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u8fd8\u67093~9\u4e5f\u53ef\u4ee5\u4f5c\u4e3a\u6587\u4ef6\u63cf\u8ff0\u7b26\u30023~9\u4f60\u53ef\u4ee5\u8ba4\u4e3a\u662f\u6267\u884c\u67d0\u4e2a\u5730\u65b9\u7684\u6587\u4ef6\u63cf\u8ff0\u7b26\uff0c\u5e38\u88ab\u7528\u6765\u4f5c\u4e3a\u4e34\u65f6\u7684\u4e2d\u95f4\u63cf\u8ff0\u7b26\u3002<\/p>\n

\u4e8c \u5b9e\u4f8b<\/p>\n

1\uff09command 2>errfile : command\u7684\u9519\u8bef\u91cd\u5b9a\u5411\u5230\u6587\u4ef6errfile\u3002
\n2\uff09command 2>&1 | …: command\u7684\u9519\u8bef\u91cd\u5b9a\u5411\u5230\u6807\u51c6\u8f93\u51fa\uff0c\u9519\u8bef\u548c\u6807\u51c6\u8f93\u51fa\u90fd\u901a\u8fc7\u7ba1\u9053\u4f20\u7ed9\u4e0b\u4e2a\u547d\u4ee4\u3002
\n3\uff09var=`command 2>&1`: command\u7684\u9519\u8bef\u91cd\u5b9a\u5411\u5230\u6807\u51c6\u8f93\u51fa\uff0c\u9519\u8bef\u548c\u6807\u51c6\u8f93\u51fa\u90fd\u8d4b\u503c\u7ed9var\u3002
\n4\uff09command 3>&2 2>&1 1>&3 | …:\u5b9e\u73b0\u6807\u51c6\u8f93\u51fa\u548c\u9519\u8bef\u8f93\u51fa\u7684\u4ea4\u6362\u3002
\n5\uff09var=`command 3>&2 2>&1 1>&3`:\u5b9e\u73b0\u6807\u51c6\u8f93\u51fa\u548c\u9519\u8bef\u8f93\u51fa\u7684\u4ea4\u6362\u3002
\n6\uff09command 2>&1 1>&2 | … (wrong…) :\u8fd9\u4e2a\u4e0d\u80fd\u5b9e\u73b0\u6807\u51c6\u8f93\u51fa\u548c\u9519\u8bef\u8f93\u51fa\u7684\u4ea4\u6362\u3002\u56e0\u4e3ashell\u4ece\u5de6\u5230\u53f3\u6267\u884c\u547d\u4ee4\uff0c\u5f53\u6267\u884c\u5b8c2>&1\u540e\uff0c\u9519\u8bef\u8f93\u51fa\u5df2\u7ecf\u548c\u6807\u51c6\u8f93\u51fa\u4e00\u6837\u7684\uff0c\u518d\u6267\u884c1>&2\u4e5f\u6ca1\u6709\u610f\u4e49\u3002<\/p>\n

\u4e09 “2>&1 file”\u548c “> file 2>&1″\u533a\u522b<\/p>\n

1\uff09cat food 2>&1 >file \uff1a\u9519\u8bef\u8f93\u51fa\u5230\u7ec8\u7aef\uff0c\u6807\u51c6\u8f93\u51fa\u88ab\u91cd\u5b9a\u5411\u5230\u6587\u4ef6file\u3002
\n2\uff09cat food >file 2>&1 \uff1a\u6807\u51c6\u8f93\u51fa\u88ab\u91cd\u5b9a\u5411\u5230\u6587\u4ef6file\uff0c\u7136\u540e\u9519\u8bef\u8f93\u51fa\u4e5f\u91cd\u5b9a\u5411\u5230\u548c\u6807\u51c6\u8f93\u51fa\u4e00\u6837\uff0c\u6240\u4ee5\u4e5f\u9519\u8bef\u8f93\u51fa\u5230\u6587\u4ef6file\u3002<\/p>\n

.\/shadowsocks.sh 2>&1 | tee file.log
\n\u5c06\u5185\u5bb9\u548c\u9519\u8bef\u8f93\u51fa\u5230\u6807\u51c6\u8f93\u51fa\u7684\u540c\u65f6\uff0c\u4fdd\u5b58\u5230\u6587\u4ef6file\u4e2d\u3002\u5982\u679c\u6587\u4ef6\u4e0d\u5b58\u5728\uff0c\u5219\u521b\u5efa\uff1b\u5982\u679c\u5df2\u7ecf\u5b58\u5728\uff0c\u5219\u8986\u76d6\u4e4b\u3002
\n\u5982\u679c\u6211\u4eec\u65e2\u60f3\u628a\u8f93\u51fa\u4fdd\u5b58\u5230\u6587\u4ef6\u4e2d\uff0c\u53c8\u60f3\u5728\u5c4f\u5e55\u4e0a\u770b\u5230\u8f93\u51fa\u5185\u5bb9\uff0c\u5c31\u53ef\u4ee5\u4f7f\u7528tee\u547d\u4ee4\u4e86\u3002tee\u547d\u4ee4\u8bfb\u53d6\u6807\u51c6\u8f93\u5165\uff0c\u628a\u8fd9\u4e9b\u5185\u5bb9\u540c\u65f6\u8f93\u51fa\u5230\u6807\u51c6\u8f93\u51fa\u548c\uff08\u591a\u4e2a\uff09\u6587\u4ef6\u4e2d<\/p>\n","protected":false},"excerpt":{"rendered":"

shell\u4e2d\u53ef\u80fd\u7ecf\u5e38\u80fd\u770b\u5230\uff1a>\/dev\/null 2>&1 \/dev\/null \u4ee3\u8868\u7a7a\u8bbe\u5907\u6587\u4ef6 > […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[],"tags":[],"class_list":["post-2172","post","type-post","status-publish","format-standard","hentry"],"_links":{"self":[{"href":"http:\/\/www.51cos.com\/index.php?rest_route=\/wp\/v2\/posts\/2172","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.51cos.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.51cos.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.51cos.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.51cos.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2172"}],"version-history":[{"count":2,"href":"http:\/\/www.51cos.com\/index.php?rest_route=\/wp\/v2\/posts\/2172\/revisions"}],"predecessor-version":[{"id":2174,"href":"http:\/\/www.51cos.com\/index.php?rest_route=\/wp\/v2\/posts\/2172\/revisions\/2174"}],"wp:attachment":[{"href":"http:\/\/www.51cos.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2172"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.51cos.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2172"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.51cos.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2172"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}