{"id":105,"date":"2013-05-09T21:05:39","date_gmt":"2013-05-09T13:05:39","guid":{"rendered":"http:\/\/coderbee.net\/?p=105"},"modified":"2013-05-09T11:26:32","modified_gmt":"2013-05-09T03:26:32","slug":"shell-%e8%84%9a%e6%9c%ac%e4%b9%8b%e6%9d%a1%e4%bb%b6%e6%b5%8b%e8%af%95%e5%92%8c%e6%b5%81%e7%a8%8b%e7%bb%93%e6%9e%84","status":"publish","type":"post","link":"https:\/\/coderbee.net\/index.php\/linux\/20130509\/105","title":{"rendered":"shell \u811a\u672c\u4e4b\u6761\u4ef6\u6d4b\u8bd5\u548c\u6d41\u7a0b\u7ed3\u6784"},"content":{"rendered":"<h2>\u6761\u4ef6\u6d4b\u8bd5<\/h2>\n<p>\u6bcf\u4e2a\u547d\u4ee4\u7ed3\u675f\u540e\uff0c\u90fd\u6709\u8fd4\u56de\u4e00\u4e2a\u7ed3\u675f\u72b6\u6001\u503c\uff0c\u503c\u4e3a0\u8868\u793a\u6267\u884c\u6210\u529f\uff0c\u975e0\u8868\u793a\u5931\u8d25\u3002\u6761\u4ef6\u6d4b\u8bd5\u5c31\u662f\u4ee5\u72b6\u6001\u8fd4\u56de\u503c\u7684\u771f\u5047\u503c\u4f5c\u4e3a\u5224\u65ad\u4f9d\u636e\uff1a\u503c\u4e3a0\u5224\u65ad\u4e3a\u771f\uff0c\u975e0\u5224\u65ad\u4e3a\u5047\u3002<\/p>\n<h3>\u6761\u4ef6\u6d4b\u8bd5\u7684\u5199\u6cd5<\/h3>\n<ul>\n<li>\u6267\u884c\u4e00\u4e2a\u547d\u4ee4\uff0c\u53ef\u4ee5\u5305\u62ec\u7ba1\u9053\u547d\u4ee4\u3002\u4f8b\u5982\uff1a <\/li>\n<\/ul>\n<pre><code>\nif  grep  -q  \"rm\"  fn.sh;  then\n     echo \"find rm command.\"\nelse\n     echo  \"not found .\"\nfi\n<\/code><\/pre>\n<ul>\n<li>\u4f20\u56de\u67d0\u4e00\u547d\u4ee4\u6267\u884c\u7ed3\u679c\u7684\u76f8\u53cd\u503c\uff1a<code>!  command<\/code>\u3002<code>!<\/code>\u4e0e\u547d\u4ee4\u4e4b\u95f4\u7528\u7a7a\u683c\u5206\u5f00\u3002<\/li>\n<\/ul>\n<pre><code>\nif  !  grep  -q  \"rm\"  fn.sh;  then\n     echo  \"not found .\"\nelse\n     echo \"find rm command.\"\nfi\n<\/code><\/pre>\n<ul>\n<li>\u4f7f\u7528\u7b26\u5408\u547d\u4ee4\uff1a(( expression ))\u3002\u5982\u679cexpression\u7684\u503c\u4e0d\u4e3a0\uff0c\u5219\u4f20\u56de\u771f\u503c\uff080\uff09\uff0c\u5426\u5219\u4f20\u56de\u5047\u503c\uff081\uff09\u3002<\/p>\n<\/li>\n<li>\n<p>\u4f7f\u7528Bash\u5173\u952e\u5b57<code>[[<\/code> \u3001<code>]]<\/code>\u7ec4\u6210\u7684\u5f0f\u5b50\uff1a<code>[[  \u5224\u65ad\u5f0f ]]<\/code>\u3002<strong>\u6ce8\u610f\uff1a<code>[[<\/code> \u7684\u540e\u9762\u3001<code>]]<\/code>\u7684\u524d\u9762\u90fd\u8981\u6709\u7a7a\u683c\u3002<\/strong><\/p>\n<\/li>\n<\/ul>\n<pre><code>\nif  [[ str > xyz ]];  then\n     echo \"str bigger than  xyz.\"\nelse\n     echo \"str not bigger than  xyz.\"\nfi\n<\/code><\/pre>\n<ul>\n<li>\u4f7f\u7528\u5185\u7f6e\u547d\u4ee4test\uff1a <code>test  \u5224\u65ad\u5f0f<\/code>\u3002<\/li>\n<\/ul>\n<pre><code>\nif  test \"str\" \\> \"xyz\";  then\n     echo \"str bigger than  xyz.\"\nelse\n     echo \"str not bigger than  xyz.\"\nfi\n<\/code><\/pre>\n<ul>\n<li>\u4f7f\u7528\u5185\u7f6e\u547d\u4ee4\uff1a<code>[]<\/code>\u3002<code>[]<\/code>\u548c<code>test<\/code>\u7684\u7528\u6cd5\u662f\u76f8\u540c\u7684\uff0c\u53ef\u4ee5\u4e92\u6362\u3002\u6ce8\u610f\uff1a<code>[<\/code> \u7684\u540e\u9762\u3001<code>]<\/code>\u7684\u524d\u9762\u90fd\u8981\u6709\u7a7a\u683c\u3002<\/li>\n<\/ul>\n<pre><code>\nif  [ \"str\" \\> \"xyz\" ];  then\n     echo \"str bigger than  xyz.\"\nelse\n     echo \"str not bigger than  xyz.\"\nfi\n<\/code><\/pre>\n<ul>\n<li>\n<p>\u4f7f\u7528<code>-a, -o<\/code>\u8fdb\u884c\u903b\u8f91\u7ec4\u5408\u3002<code>-a<\/code>\u662f\u903b\u8f91\u4e0e\uff0c<code>-o<\/code>\u903b\u8f91\u6216\u3002\u4f8b\u5982\uff1a<code>[ -f filename -a -x filename ]<\/code>\uff0c\u5982\u679cfilename\u53ef\u8bfb\u4e14\u53ef\u6267\u884c\u5219\u4e3a\u771f\u3002<\/p>\n<\/li>\n<li>\n<p><strong>\u6ce8\u610f\uff1a<\/strong><\/p>\n<ul>\n<li><code>test<\/code>\u548c<code>[]<\/code>\u90fd\u9700\u8981\u5bf9Bash\u7279\u6b8a\u5b57\u7b26\u8fdb\u884c\u8f6c\u4e49\uff1b\u800c<code>[[]]<\/code>\u4e0d\u9700\u8981\uff0c<code>&lt;, &gt;, &amp;&amp;,  ||<\/code>\u90fd\u53ef\u4ee5\u5728\u5176\u4e2d\u81ea\u7531\u4f7f\u7528\u3002<\/li>\n<li>\u5728<code>[[  \u5224\u65ad\u5f0f ]]<\/code>\u4e2d\uff0c\u5982\u679c\u4f7f\u7528<code>==,  !=<\/code>\uff0c\u4e14\u5728\u8fd9\u4e24\u4e2a\u8fd0\u7b97\u7b26\u53f3\u8fb9\u7684\u5b57\u7b26\u4e32\u6ca1\u6709\u52a0\u4e0a\u5355\u5f15\u53f7\u6216\u53cc\u5f15\u53f7\uff0c\u5219<code>==, !=<\/code>\u4f1a\u89c6\u4e3a\u9700\u8981\u5339\u914d\u8be5\u5b57\u7b26\u4e32\u6240\u5f62\u6210\u7684\u201c\u6837\u5f0f\u201d\uff0c\u5982\u679c\u5339\u914d\uff0c\u8fd4\u56de0\uff0c\u5426\u5219\u8fd4\u56de1\u3002<\/li>\n<li>\u5728<code>[[  \u5224\u65ad\u5f0f ]]<\/code>\u4e2d\uff0c<code>=~<\/code>\u7684\u53f3\u8fb9\u653e\u7f6e\u8981\u5339\u914d\u7684\u6837\u5f0f\u3002\u6837\u5f0f\u4e0d\u80fd\u7528\u5f15\u53f7\u5f15\u8d77\uff0c\u5426\u5219\u4e0d\u4f1a\u88ab\u5f53\u4f5c\u6837\u5f0f\u5339\u914d\u3002<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p><!--more--><\/p>\n<h3>\u6761\u4ef6\u5224\u65ad\u5f0f<\/h3>\n<h4>\u6587\u4ef6\u7684\u6761\u4ef6\u5224\u65ad\u5f0f<\/h4>\n<pre><code>\n\u5224\u65ad\u5f0f                    \u5728\u4ec0\u4e48\u60c5\u51b5\u4e0b\u4e3a\u771f\n-a  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\n-b  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f\u5757\u8bbe\u5907\u6587\u4ef6\n-c  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f\u5b57\u7b26\u8bbe\u5907\u6587\u4ef6\n-d  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f\u76ee\u5f55\n-e  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\n-f  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f\u666e\u901a\u6587\u4ef6\n-g  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u8bbe\u7f6e\u4e86set group id \u5c5e\u6027\n-h  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f\u7b26\u53f7\u94fe\u63a5\u6587\u4ef6\n-k  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u8bbe\u7f6e\u4e86 sticky \u5c5e\u6027\n-p  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f\u7ba1\u9053\u6587\u4ef6\uff08FIFO\uff09\n-r  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u5177\u6709\u53ef\u8bfb\u5c5e\u6027\n-s  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u7684\u957f\u5ea6\u5927\u4e8e0\n-t  \u6587\u4ef6\u63cf\u8ff0\u7b26         \u5982\u679c\u6587\u4ef6\u63cf\u8ff0\u7b26\u662f\u5f00\u542f\u7684\uff0c\u4e14\u94fe\u63a5\u4e86\u4e00\u4e2a\u7ec8\u7aef\n-u  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u8bbe\u7f6e\u4e86set user id \u5c5e\u6027\n-w  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u5177\u6709\u53ef\u5199\u5c5e\u6027\n-x  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u5177\u6709\u53ef\u6267\u884c\u5c5e\u6027\n-O  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u4e3a\u6e38\u620f\u7684\u4f7f\u7528\u8005id\u6240\u62e5\u6709\n-G  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u4e3a\u6e38\u620f\u7684\u7fa4\u7ec4id\u6240\u62e5\u6709\n-L  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f\u7b26\u53f7\u94fe\u63a5\u6587\u4ef6\n-S  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u662f socket \u6587\u4ef6\n-N  filename            \u5982\u679c\u6587\u4ef6\u5b58\u5728\uff0c\u4e14\u8be5\u6587\u4ef6\u81ea\u4e0a\u6b21\u8bfb\u53d6\u540e\uff0c\u66fe\u4fee\u6539\u8fc7\nfile1  -nt  file2         \u5982\u679cfil1\u6bd4file2\u65b0\uff1b\u6216file1\u5b58\u5728\uff0cfile2\u4e0d\u5b58\u5728\nfile1  -ot  file2         \u5982\u679cfil1\u6bd4file2\u65e7\uff1b\u6216file2\u5b58\u5728\uff0cfile1\u4e0d\u5b58\u5728\nfile1  -ef  file2         \u5982\u679cfil1\u6bd4file2\u5f15\u7528\u5230\u7cfb\u7edf\u7684\u8bbe\u5907\u548cinode\u7f16\u53f7\n<\/code><\/pre>\n<h4>\u5b57\u7b26\u4e32\u7684\u6761\u4ef6\u5224\u65ad\u5f0f<\/h4>\n<pre><code>\n\u5224\u65ad\u5f0f                    \u5728\u4ec0\u4e48\u60c5\u51b5\u4e0b\u4e3a\u771f\n-z  str                     \u5982\u679c\u5b57\u7b26\u4e32\u957f\u5ea6\u4e3a0\n-n  str                    \u5982\u679c\u5b57\u7b26\u4e32\u957f\u5ea6\u4e0d\u4e3a0\nstr                         \u5982\u679c\u5b57\u7b26\u4e32\u957f\u5ea6\u4e0d\u4e3a0\nstr1 == str2           \u5982\u679c\u4e24\u4e2a\u5b57\u7b26\u4e32\u76f8\u540c\nstr1 = str2             \u5982\u679c\u4e24\u4e2a\u5b57\u7b26\u4e32\u76f8\u540c\nstr1 != str2            \u5982\u679c\u4e24\u4e2a\u5b57\u7b26\u4e32\u4e0d\u76f8\u540c \nstr1 < str2             \u5982\u679cstr1\u5c0f\u4e8estr2\nstr1 > str2             \u5982\u679cstr1\u5927\u4e8estr2\n<\/code><\/pre>\n<p>\u6ce8\u610f\uff1a\u5982\u679c<code>&lt;,  &gt;<\/code>\u51fa\u73b0\u5728<code>test,  []<\/code>\u4e2d\uff0c\u8981\u8fdb\u884c\u8f6c\u4e49\u3002<\/p>\n<h4>\u6570\u503c\u7684\u6761\u4ef6\u5224\u65ad\u5f0f<\/h4>\n<pre><code>\n\u5224\u65ad\u5f0f                     \u5728\u4ec0\u4e48\u60c5\u51b5\u4e0b\u4e3a\u771f\nvar1  -eq  var2         var1\u548cvar2\u503c\u76f8\u7b49\nvar1  -ne  var2         var1\u548cvar2\u503c\u4e0d\u76f8\u7b49 \nvar1  -lt  var2           var1\u7684\u503c\u5c0f\u4e8evar2\u7684\u503c\nvar1  -le  var2          var1\u7684\u503c\u5c0f\u4e8e\u7b49\u4e8evar2\u7684\u503c\nvar1  -gt  var2          var1\u7684\u503c\u5927\u4e8evar2\u7684\u503c\nvar1  -ge  var2         var1\u7684\u503c\u5927\u4e8e\u7b49\u4e8evar2\u7684\u503c\n<\/code><\/pre>\n<h2>\u6d41\u7a0b\u63a7\u5236<\/h2>\n<h3>if \u6761\u4ef6\u5224\u65ad<\/h3>\n<p>\u5b8c\u6574\u8bed\u6cd5\uff1a<\/p>\n<pre><code>\nif  \u6761\u4ef6\u6d4b\u8bd51;  then\n     cmd1\nelif  \u6761\u4ef6\u6d4b\u8bd52;  then\n     cmd2\nelse\n     cmd3\nfi\n<\/code><\/pre>\n<h3>case \u6761\u4ef6\u5224\u65ad<\/h3>\n<h4>\u5b8c\u6574\u8bed\u6cd5<\/h4>\n<pre><code>\ncase  \u5f85\u6d4b\u8bd5\u9879  in\n     \u6837\u5f0f\u4e321)   \u547d\u4ee4\u533a\u57df1;;\n     \u6837\u5f0f\u4e322)   \u547d\u4ee4\u533a\u57df2;;\n     \u6837\u5f0f\u4e323)   \u547d\u4ee4\u533a\u57df3;;\n     ... \n     *)   \u547d\u4ee4\u533a\u57df;;\nesac\n<\/code><\/pre>\n<h4>\u8bf4\u660e<\/h4>\n<ul>\n<li>\u547d\u4ee4\u533a\u57df\u53ef\u4ee5\u6709\u591a\u6761\u547d\u4ee4\uff0c\u4f46\u6700\u540e\u4e00\u6761\u547d\u4ee4\u5fc5\u987b\u4ee5<code>;;<\/code>\u7ed3\u675f\u3002<\/li>\n<li>\u6837\u5f0f\u4e32\u53ef\u7528\u5b57\u7b26\u4e32\u548c\u901a\u914d\u7b26\u7ec4\u6210\uff0c\u9ed8\u8ba4\u4e0d\u533a\u5206\u5927\u5c0f\u5199\u3002<\/li>\n<li>\u5982\u679c\u6837\u5f0f\u4e32\u884c\u4e2d\u6709\u51e0\u4e2a\u5b57\u7b26\u4e32\u8981\u5bf9\u6bd4\uff0c\u7528<code>|<\/code>\u9694\u5f00\u3002<code>|<\/code>\u8868\u793a\u6216\u7684\u610f\u601d\u3002<\/li>\n<li>\u6837\u5f0f\u4e32\u53ef\u4ee5\u5199\u6210 <code>(\u6837\u5f0f\u4e32\u884c)<\/code> \uff0c\u6216\u7701\u7565\u5de6\u8fb9\u7684\u62ec\u53f7\uff0c\u5199\u6210 <code>\u6837\u5f0f\u4e32\u884c)<\/code>  \u3002\u63a8\u8350\u540e\u8005\u3002<\/li>\n<li>\u6837\u5f0f<code>*)<\/code>\u901a\u5e38\u653e\u5728case\u6700\u540e\u4e00\u4e2a\u533a\u57df\uff0c\u7528\u6765\u6355\u6349\u4e0d\u7b26\u5408\u6307\u5b9a\u6837\u5f0f\u7684\u5176\u4ed6\u6240\u6709\u60c5\u51b5\u3002<\/li>\n<\/ul>\n<h4>\u6837\u5f0f\u4e32\u7ec4\u6210<\/h4>\n<ul>\n<li>\u5b57\u7b26\u4e32\u3002<\/li>\n<li>\u901a\u914d\u7b26\uff1a<code>*<\/code>\u8868\u793a\u4efb\u610f\u5b57\u7b26\u4e32\uff1b<code>?<\/code>\u8868\u793a\u5355\u4e2a\u5b57\u7b26\u3002<\/li>\n<li>\u5b57\u7b26\u96c6\u5408\uff1a<code>[]<\/code>\u3002<\/li>\n<li>\u9879\u76ee\u5206\u9694\u7b26<code>|<\/code>\u3002<\/li>\n<\/ul>\n<p>\u6253\u5f00Bash\u7684\u9009\u9879<code>extglob<\/code>\uff0c\u8fd8\u53ef\u4ee5\u652f\u6301\u51e0\u79cd\u9ad8\u7ea7\u6837\u5f0f\u5339\u914d\uff1a<code>shopt  -s  extglob<\/code><\/p>\n<ul>\n<li><code>?(\u6837\u5f0f\u4e32\u884c)<\/code>\uff1a\u5982\u679c\u7b26\u54080\u62161\u4e2a\u62ec\u53f7\u91cc\u7684\u6837\u5f0f\u4e32\u884c\uff0c\u7b97\u5339\u914d\u3002<\/li>\n<li><code>*(\u6837\u5f0f\u4e32\u884c)<\/code>\uff1a\u5982\u679c\u7b26\u54080\u4e2a\u4ee5\u4e0a\u62ec\u53f7\u91cc\u7684\u6837\u5f0f\u4e32\u884c\uff0c\u7b97\u5339\u914d\u3002<\/li>\n<li><code>+(\u6837\u5f0f\u4e32\u884c)<\/code>\uff1a\u5982\u679c\u7b26\u54081\u4e2a\u4ee5\u4e0a\u62ec\u53f7\u91cc\u7684\u6837\u5f0f\u4e32\u884c\uff0c\u7b97\u5339\u914d\u3002<\/li>\n<li><code>@(\u6837\u5f0f\u4e32\u884c)<\/code>\uff1a\u5982\u679c\u7b26\u5408\u62ec\u53f7\u91cc\u7684\u6837\u5f0f\u4e32\u884c\u4e2d\u7684\u4e00\u4e2a\uff0c\u7b97\u5339\u914d\u3002<\/li>\n<li><code>\uff01(\u6837\u5f0f\u4e32\u884c)<\/code>\uff1a\u53ea\u8981\u662f\u4e0d\u51fa\u73b0\u5728\u62ec\u53f7\u91cc\u7684\u6837\u5f0f\u4e32\u884c\uff0c\u7b97\u5339\u914d\u3002<\/li>\n<\/ul>\n<p>\u9ad8\u7ea7\u6837\u5f0f\uff0c\u9664\u4e86\u5728case\u4e2d\u4f7f\u7528\uff0c\u8fd8\u53ef\u4ee5\u7528\u5728<code>[[]]<\/code>\u6761\u4ef6\u5224\u65ad\u4e2d\u3002<\/p>\n<h3>for\u5faa\u73af<\/h3>\n<h4>\u65b9\u5f0f1\uff1a\u904d\u5386\u4e32\u884c<\/h4>\n<pre><code>\nfor  \u53d8\u91cf  in  \u4e32\u884c\ndo\n     commands\ndone\n<\/code><\/pre>\n<p>\u4e32\u884c\u662f\u7531\u5b57\u7b26\u4e32\u7ec4\u6210\uff0c\u5f7c\u6b64\u7528 <code>$IFS<\/code> \u6240\u5b9a\u4e49\u7684\u5206\u5272\u5b57\u7b26\u9694\u5f00\u3002<\/p>\n<p>\u4e3e\u4f8b\uff0c\u904d\u5386\u547d\u4ee4\u884c\u53c2\u6570<code>for  i  in  $@<\/code>\uff0c\u5904\u7406\u5f53\u524d\u76ee\u5f55\uff1a<code>for  f  in  $(ls .)<\/code>\u3002<\/p>\n<h4>\u65b9\u5f0f2\uff1aC-style for\u5faa\u73af<\/h4>\n<pre><code>\nfor  ((\u521d\u59cb\u6761\u4ef6;  \u7ec8\u6b62\u6761\u4ef6;  \u6539\u52a8\u9879))\ndo\n     commands\ndone\n<\/code><\/pre>\n<h4>\u65b9\u5f0f3\uff1a\u6b7b\u5faa\u73af<\/h4>\n<pre><code>\nfor  ((;  1;  ))\ndo\n     commands\ndone\n<\/code><\/pre>\n<h3>while \u5faa\u73af<\/h3>\n<p>\u8bed\u6cd5\uff1a<\/p>\n<pre><code>\nwhile  \u6761\u4ef6\u6d4b\u8bd5\ndo\n     cmds\ndone\n<\/code><\/pre>\n<p>while\u5faa\u73af\u642d\u914d\u8f93\u5165\u91cd\u5b9a\u5411\u8bfb\u53d6\u6587\u4ef6\u5185\u5bb9\uff1a<\/p>\n<pre><code>\nwhile  read  line\ndo\n     echo  $line\ndone  <  input_file\n<\/code><\/pre>\n<h3>until \u5faa\u73af<\/h3>\n<p>whlie\u5faa\u73af\u7684\u6761\u4ef6\u6d4b\u8bd5\u662f\u6d4b\u8bd5\u771f\u503c\uff0cuntil\u5faa\u73af\u662f\u6d4b\u8bd5\u5047\u503c\uff0c\u503c\u4e3a\u5047\u5219\u8fdb\u5165\u5faa\u73af\u3002<\/p>\n<p>\u8bed\u6cd5\uff1a<\/p>\n<pre><code>\nuntil  \u6761\u4ef6\u6d4b\u8bd5\ndo\n     cmds\ndone\n<\/code><\/pre>\n<h3>select \u8bed\u53e5<\/h3>\n<p>select\u547d\u4ee4\u53ef\u5efa\u7acb\u7b80\u6613\u7684\u5217\u8868\uff0c\u8bed\u6cd5\u7ed3\u6784\u548cfor\u5faa\u73af\u4e00\u6837\u3002<\/p>\n<pre><code>\nfor  \u9009\u9879\u53d8\u91cf  in  \u4e32\u884c\ndo\n     cmds\ndone\n<\/code><\/pre>\n<p>\u8bf4\u660e\uff1a<\/p>\n<ul>\n<li>select\u547d\u4ee4\u5efa\u7acb\u4e00\u4e2a\u9009\u62e9\u5217\u8868\u3002\u5217\u8868\u7684\u9009\u9879\u7531\u4e32\u884c\u4e2d\u7684\u5404\u4e2a\u5b57\u6bb5\u7ec4\u6210\u3002\u5217\u8868\u63d0\u793a\u7b26\u53f7\u7531Bash\u7684\u5185\u7f6e\u53d8\u91cf<code>PS3<\/code>\u5b9a\u4e49\uff0c\u53ef\u6539\u53d8\u3002select\u4f1a\u7ed9\u5404\u4e2a\u9009\u9879\u4e00\u4e2a\u7f16\u53f7\uff0c\u7f16\u53f7\u75311\u5f00\u59cb\u9012\u589e\u3002\u5f53\u7528\u6237\u8f93\u5165\u7f16\u53f7\uff0c\u9009\u62e9\u5176\u4e2d\u4e00\u9879\u65f6\uff0c\u8be5\u9009\u9879\u7684\u5185\u5bb9\u5c31\u8bbe\u7f6e\u7ed9\u9009\u9879\u53d8\u91cf\uff0c\u952e\u5165\u7684\u7f16\u53f7\u503c\u653e\u5165\u53d8\u91cf<code>REPLY<\/code>\u3002<\/li>\n<li>\u7528\u6237\u6bcf\u8f93\u5165\u4e00\u6b21\u7f16\u53f7\uff0c\u5c31\u6267\u884c\u4e00\u6b21\u547d\u4ee4\u533a\u57df\u3002<\/li>\n<li>\u547d\u4ee4\u6267\u884c\u5b8c\u540e\uff0c\u91cd\u65b0\u6267\u884cselect\u547d\u4ee4\uff0c\u518d\u6b21\u663e\u793a\u5217\u8868\u3002<\/li>\n<\/ul>\n<h3>break, continue<\/h3>\n<p>\u5728<code>for,  while,  until,  select<\/code>\u5faa\u73af\u4e2d\uff0c\u53ef\u4ee5\u7528<code>break<\/code>\u8df3\u51fa\u5faa\u73af\uff0c<code>break<\/code>\u540e\u9762\u53ef\u8ddf\u4e00\u4e2a\u5c42\u6570n\uff08n\u4e00\u5b9a\u8981\u5927\u4e8e\u7b49\u4e8e1\uff09\uff0c\u8868\u793a\u8df3\u51fa\u5faa\u73af\u7684\u5c42\u6570\uff1b\u7528<code>continue<\/code>\u53ef\u8df3\u8fc7\u672c\u6b21\u5faa\u73af\u3002<\/p>\n<hr\/>\n<p>\u6b22\u8fce\u5173\u6ce8\u6211\u7684\u5fae\u4fe1\u516c\u4f17\u53f7: <strong>coderbee\u7b14\u8bb0<\/strong>\uff0c\u53ef\u4ee5\u66f4\u53ca\u65f6\u56de\u590d\u4f60\u7684\u8ba8\u8bba\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" width=\"258\" height=\"258\" src=\"https:\/\/coderbee.net\/wp-content\/uploads\/2019\/01\/coderbee-note.jpg\" class=\"alignnone size-full wp-image-1707\"><\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u6761\u4ef6\u6d4b\u8bd5 \u6bcf\u4e2a\u547d\u4ee4\u7ed3\u675f\u540e\uff0c\u90fd\u6709\u8fd4\u56de\u4e00\u4e2a\u7ed3\u675f\u72b6\u6001\u503c\uff0c\u503c\u4e3a0\u8868\u793a\u6267\u884c\u6210\u529f\uff0c\u975e0\u8868\u793a\u5931 &hellip; <a href=\"https:\/\/coderbee.net\/index.php\/linux\/20130509\/105\">\u7ee7\u7eed\u9605\u8bfb <span class=\"meta-nav\">&rarr;<\/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":[3],"tags":[35,36],"_links":{"self":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts\/105"}],"collection":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/comments?post=105"}],"version-history":[{"count":4,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts\/105\/revisions"}],"predecessor-version":[{"id":110,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/posts\/105\/revisions\/110"}],"wp:attachment":[{"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/media?parent=105"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/categories?post=105"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/coderbee.net\/index.php\/wp-json\/wp\/v2\/tags?post=105"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}