{"id":61698,"date":"2026-01-18T11:59:25","date_gmt":"2026-01-18T03:59:25","guid":{"rendered":"https:\/\/www.wsisp.com\/helps\/61698.html"},"modified":"2026-01-18T11:59:25","modified_gmt":"2026-01-18T03:59:25","slug":"%e3%80%90linux%e3%80%91%e7%8e%af%e5%a2%83%e5%8f%98%e9%87%8f","status":"publish","type":"post","link":"https:\/\/www.wsisp.com\/helps\/61698.html","title":{"rendered":"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf"},"content":{"rendered":"<h2>\u5f15\u5165<\/h2>\n<p>\u6211\u4eec\u5728\u547d\u4ee4\u884c\u4e2d\u6267\u884c\u5982\u4e0b\u547d\u4ee4&#xff1a;<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession15$ echo $PATH<br \/>\n\/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin<\/p>\n<p>\u7cfb\u7edf\u4f1a\u8f93\u51fa\u4e00\u6bb5\u7531:\u9694\u5f00\u7684\u8def\u5f84\u3002\u8fd9\u5176\u5b9e\u5c31\u662f\u6211\u4eec\u6bcf\u5929\u90fd\u5728\u7528\u7684\u4e1c\u897f&#xff0c;\u53ea\u662f\u6211\u4eec\u5e76\u4e0d\u81ea\u77e5\u3002\u5f53\u6211\u4eec\u8f93\u5165ls&#xff0c;ps&#xff0c;gcc\u547d\u4ee4\u65f6&#xff0c;\u7cfb\u7edf\u4fbf\u4f1a\u5728\u8fd9\u4e9b\u8def\u5f84\u4e0b\u53bb\u627e\u8fd9\u4e9b\u547d\u4ee4\u7684\u53ef\u6267\u884c\u6587\u4ef6&#xff0c;\u5e76\u6267\u884c\u3002\u8fd9\u5c31\u662f\u914d\u7f6e\u73af\u5883\u53d8\u91cf\u7684\u597d\u5904&#xff0c;\u6211\u4eec\u4e0d\u7528\u6bcf\u6b21\u8f93\u5165\u547d\u4ee4\u65f6\u90fd\u5e26\u4e0a\u5197\u6742\u7684\u8def\u5f84&#xff0c;\u73af\u5883\u53d8\u91cf\u4f1a\u544a\u8bc9\u7cfb\u7edf\u53bb\u54ea\u627e\u7528\u5230\u7684\u547d\u4ee4\u3002<\/p>\n<h3>\u5b9a\u4e49<\/h3>\n<p>\u73af\u5883\u53d8\u91cf&#xff08;Environment Variables&#xff09;\u662f\u64cd\u4f5c\u7cfb\u7edf\u5728\u8fdb\u7a0b\u542f\u52a8\u65f6\u4f20\u9012\u7684\u4e00\u7ec4\u52a8\u6001\u952e\u503c\u5bf9&#xff08;key&#061;value&#xff09;\u4f8b\u5982&#xff1a;PATH&#061;\/usr\/bin:\/bin &#xff08;key\u662fPATH&#xff0c;\u503c&#xff1a;\/usr\/bin:\/bin &#xff09;&#xff0c;\u7528\u4e8e\u914d\u7f6e\u8fdb\u7a0b\u7684\u8fd0\u884c\u73af\u5883\u3002\u8fd9\u4e9b\u5b57\u7b26\u4e32\u5f62\u5f0f\u7684\u53d8\u91cf\u88ab shell\u3001\u5e94\u7528\u7a0b\u5e8f\u548c\u7cfb\u7edf\u670d\u52a1\u5e7f\u6cdb\u4f7f\u7528&#xff0c;\u4e3b\u8981\u529f\u80fd\u5305\u62ec\u63a7\u5236\u7a0b\u5e8f\u884c\u4e3a\u3001\u6307\u5b9a\u8def\u5f84\u4ee5\u53ca\u6807\u8bc6\u7528\u6237\u8eab\u4efd\u7b49\u3002<\/p>\n<p>\u5e38\u89c1\u793a\u4f8b&#xff1a;<\/p>\n<ul>\n<li>PATH&#xff1a;\u6307\u5b9a shell \u67e5\u627e\u53ef\u6267\u884c\u547d\u4ee4\u7684\u76ee\u5f55\u8def\u5f84<\/li>\n<li>HOME&#xff1a;\u6807\u8bc6\u5f53\u524d\u7528\u6237\u7684\u4e3b\u76ee\u5f55\u4f4d\u7f6e<\/li>\n<li>USER&#xff1a;\u8bb0\u5f55\u5f53\u524d\u767b\u5f55\u7684\u7528\u6237\u540d\u4fe1\u606f<\/li>\n<\/ul>\n<p>\u73af\u5883\u53d8\u91cf\u7684\u4f20\u9012\u673a\u5236\u662f\u901a\u8fc7\u7236\u8fdb\u7a0b\u521b\u5efa&#xff0c;\u5e76\u7ecf\u7531 fork() \u548c execve() \u7cfb\u7edf\u8c03\u7528\u81ea\u52a8\u4f20\u9012\u7ed9\u5b50\u8fdb\u7a0b&#xff0c;\u6784\u6210\u4e86\u8fdb\u7a0b\u95f4\u4f20\u9012\u4e0a\u4e0b\u6587\u4fe1\u606f\u7684\u91cd\u8981\u901a\u9053\u3002<\/p>\n<h2 style=\"background-color:transparent\">main\u51fd\u6570\u7684\u53c2\u6570<\/h2>\n<h4>_start<\/h4>\n<p>main\u51fd\u6570\u5e26\u53c2\u6570\u5417&#xff0c;\u5e73\u65f6\u6211\u4eec\u5e76\u6ca1\u6709\u53bb\u5e26\u53c2\u6570&#xff0c;\u5176\u5b9emain\u51fd\u6570\u662f\u5e26\u53c2\u6570\u7684&#xff0c;main\u51fd\u6570\u4e5f\u662f\u4f1a\u88ab\u8c03\u7528\u7684&#xff0c;\u5e73\u65f6\u6211\u4eec\u8bf4main\u51fd\u6570\u662f\u7a0b\u5e8f\u7684\u5165\u53e3&#xff0c;\u5176\u5b9emain\u51fd\u6570\u53ea\u662f\u6211\u4eec\u5199\u7684\u7a0b\u5e8f\u7684\u5165\u53e3&#xff0c;\u6211\u4eec\u5199\u7684\u7a0b\u5e8f\u5176\u5b9e\u8fd8\u4f1a\u5728\u7f16\u8bd1\u65f6\u8fd8\u4f1a\u7ecf\u8fc7\u4e00\u7cfb\u5217\u201d\u5305\u88c5\u201c\u6dfb\u52a0\u4e00\u4e9b\u4e1c\u897f\u624d\u80fd\u6210\u4e3a\u53ef\u6267\u884c\u7a0b\u5e8f&#xff1b;\u7a0b\u5e8f\u7684\u8d77\u70b9\u5728Linux\u4e2d\u662f_start&#xff0c;_start\u4f1a\u8c03\u7528__libc_start_main\u4ece\u5185\u6838\u4e2d\u83b7\u53d6\u53c2\u6570\u4f20\u7ed9main\u3002<\/p>\n<p>\u5efa\u7acb\u4e00\u4e2a.c\u6587\u4ef6,\u7f16\u8bd1&#xff1b;\u5c06\u53ef\u6267\u884c\u7a0b\u5e8f\u8f6c\u6210\u6c47\u7f16\u8bed\u8a00&#xff1a;<\/p>\n<p> objdump -d -M intel code<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" alt=\"\" height=\"446\" src=\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/01\/20260118035923-696c5a9ba9d4a.png\" width=\"902\" \/><\/p>\n<p>\u5728\u8fd9\u5176\u4e2d\u627e\u5230_start:<\/p>\n<p>0000000000001060 &lt;_start&gt;:<br \/>\n    1060:f3 0f 1e fa          endbr64<br \/>\n    1064:31 ed                xor    ebp,ebp<br \/>\n    1066:49 89 d1             mov    r9,rdx<br \/>\n    1069:5e                   pop    rsi<br \/>\n    106a:48 89 e2             mov    rdx,rsp<br \/>\n    106d:48 83 e4 f0          and    rsp,0xfffffffffffffff0<br \/>\n    1071:50                   push   rax<br \/>\n    1072:54                   push   rsp<br \/>\n    1073:45 31 c0             xor    r8d,r8d<br \/>\n    1076:31 c9                xor    ecx,ecx<br \/>\n    1078:48 8d 3d ca 00 00 00 lea    rdi,[rip&#043;0xca]        # 1149 &lt;main&gt;<br \/>\n    107f:ff 15 53 2f 00 00    call   QWORD PTR [rip&#043;0x2f53]        # 3fd8 &lt;__libc_start_main&#064;GLIBC_2.34&gt;<br \/>\n    1085:f4                   hlt<br \/>\n    1086:66 2e 0f 1f 84 00 00 cs nop WORD PTR [rax&#043;rax*1&#043;0x0]<br \/>\n    108d:00 00 00 <\/p>\n<p>\u6211\u4eec\u4f1a\u53d1\u73b0_start\u8c03\u7528\u4e86\u4e00\u4e2a\u53eb__libc_start_main\u7684\u4e1c\u897f&#xff0c;\u8fd9\u4e2a\u00a0\u662f glibc \u5e93\u4e2d\u63d0\u4f9b\u7684\u542f\u52a8\u51fd\u6570&#xff0c;\u5b83\u7684\u4f5c\u7528\u5c31\u662f\u63a5\u6536 main \u5730\u5740\u4f5c\u4e3a\u53c2\u6570&#xff0c;\u7136\u540e\u8c03\u7528 main \u51fd\u6570\u3002\u4ece\u8fd9\u91cc\u5c31\u53ef\u4ee5\u770b\u51famain\u51fd\u6570\u5e76\u4e0d\u662f\u7a0b\u5e8f\u7684\u8d77\u70b9&#xff0c;\u5b83\u4e5f\u4f1a\u88ab\u8c03\u7528\u3002<\/p>\n<p>\/\/\u4f2a\u4ee3\u7801<br \/>\n _start() {<br \/>\n    int ret &#061; 0;<br \/>\n    int arg_count &#061; 0;<\/p>\n<p>    \/\/ \u8fd9\u91cc\u786c\u7f16\u7801\u53c2\u6570\u6570\u91cf\u4e3a 3&#xff0c;\u4e5f\u53ef\u4ee5\u6362\u6210\u5b9e\u9645\u8fd0\u884c\u65f6\u83b7\u53d6\u7684\u503c<br \/>\n    arg_count &#061; 3;<\/p>\n<p>    if (arg_count &#061;&#061; 0) {<br \/>\n        ret &#061; main();<br \/>\n    } else if (arg_count &#061;&#061; 2) {<br \/>\n        ret &#061; main(argc, argv);<br \/>\n    } else {<br \/>\n        ret &#061; main(argc, argv, env);<br \/>\n    }<\/p>\n<p>}<\/p>\n<h4 style=\"background-color:transparent\">\u547d\u4ee4\u884c\u53c2\u6570<\/h4>\n<p>\u4e8b\u5b9e\u4e0a&#xff0c;main\u51fd\u6570\u662f\u5e26\u53c2\u6570\u7684\u3002<\/p>\n<p>int main(int argc,char* argv[])<br \/>\n{<\/p>\n<p>        return 0;<br \/>\n}<\/p>\n<p>\u5e73\u65f6\u6211\u4eec\u4f7f\u7528main\u51fd\u6570\u65f6&#xff0c;\u6211\u4eec\u5e76\u6ca1\u6709\u5e26\u53c2\u6570&#xff1b; \u8fd9\u662f\u56e0\u4e3a\u5f53\u6211\u4eec\u4e0d\u4e3b\u52a8\u4ece\u547d\u4ee4\u884c\u4f20\u9012\u53c2\u6570\u65f6&#xff0c;\u64cd\u4f5c\u7cfb\u7edf\u4f1a\u9ed8\u8ba4\u8c03\u7528\u00a0main&#xff0c;\u5e76\u5c06\u00a0argc\u00a0\u8bbe\u4e3a 1&#xff0c;argv[0]\u00a0\u8d4b\u503c\u4e3a\u7a0b\u5e8f\u81ea\u8eab\u7684\u540d\u5b57&#xff08;\u8def\u5f84&#xff09;\u3002<\/p>\n<p>main\u51fd\u6570\u7684\u8fd9\u4e24\u4e2a\u53c2\u6570\u662f\u4ec0\u4e48\u5462&#xff1f;\u4ed4\u7ec6\u89c2\u5bdf\u6211\u4eec\u4f1a\u53d1\u73b0\u8fd9\u4e24\u4e2a\u53c2\u6570\u7684\u540d\u5b57\u5f88\u76f8\u4f3c&#xff0c;\u7b2c\u4e8c\u4e2a\u53c2\u6570argv\u662f\u4e00\u4e2a\u5b57\u7b26\u4e32\u6307\u9488\u6570\u7ec4&#xff0c;\u800cargc\u5c31\u662f\u8fd9\u4e2a\u6307\u9488\u6570\u7ec4\u7684\u5143\u7d20\u4e2a\u6570\u3002<\/p>\n<p>\u5f53\u6211\u4eec\u5728\u547d\u4ee4\u884cls -n\u65f6&#xff0c;\u5c31\u4f1a\u7ed9ls\u547d\u4ee4\u7684\u6267\u884c\u7a0b\u5e8f\u4e2d\u7684main\u51fd\u6570\u4f20\u5165\u201dls -n\u201c\u4f5c\u4e3a\u53c2\u6570&#xff0c;bash\u4f1a\u5c06\u8fd9\u4e9b\u547d\u4ee4\u548c\u9009\u9879\u505a\u5206\u5272&#xff0c;\u6700\u7ec8\u4f20\u7ed9\u00a0argv\u6570\u7ec4\u4e2d\u3002argv[0]&#061;\u201dls\u201c,argv[1]&#061;&#034;-n&#034;,argv[argc]&#061;NULL\u3002<\/p>\n<p>\u6211\u4eec\u6765\u5b9e\u8df5\u4e00\u4e0b&#xff1a;<\/p>\n<p>#include&lt;stdio.h&gt;<\/p>\n<p>int main(int argc,char* argv[])<br \/>\n{<br \/>\n        for(int i &#061; 0; i&lt; argc;i&#043;&#043;)<br \/>\n        {<br \/>\n                printf(&#034;argv[%d]:%s\\\\n&#034;,i,argv[i]);<\/p>\n<p>        }<\/p>\n<p>        \/\/printf(&#034;It&#039;s pretty!\\\\n&#034;);<br \/>\n        return 0;<br \/>\n}<br \/>\n~<br \/>\n~                                <\/p>\n<p>\u7f16\u8bd1\u4e4b\u540e\u8fd0\u884c&#xff1a;<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ .\/code a b c d<br \/>\nargv[0]:.\/code<br \/>\nargv[1]:a<br \/>\nargv[2]:b<br \/>\nargv[3]:c<br \/>\nargv[4]:d<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" alt=\"\" height=\"338\" src=\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/01\/20260118035923-696c5a9bd86d9.png\" width=\"329\" \/><\/p>\n<p>\u7cfb\u7edf\u4f1a\u901a\u8fc7.\/code\u627e\u5230\u5f53\u524d\u76ee\u5f55\u6211\u4eec\u7684\u53ef\u6267\u884c\u7a0b\u5e8fcode&#xff0c;\u5c06\u6211\u4eec\u8f93\u5165\u7684\u53c2\u6570\u5168\u90e8\u4f20\u7ed9\u53ef\u6267\u884c\u7a0b\u5e8f&#xff0c;\u540c\u65f6\u6211\u4eec\u8f93\u5165\u7684\u4e1c\u897f\u4f1a\u88abbash\u505a\u5207\u5206\u3002<\/p>\n<p>\u6211\u4eec\u628aargv\u79f0\u4f5c<span style=\"background-color:#a2e043\">\u547d\u4ee4\u884c\u53c2\u6570\u8868<\/span>&#xff0c;\u8fdb\u7a0b\u542f\u52a8\u65f6&#xff0c;bash\u5c31\u4f1a\u7ef4\u62a4\u4e00\u4e2a\u547d\u4ee4\u884c\u53c2\u6570\u8868&#xff0c;\u5c06\u53c2\u6570\u4ee5\u5b57\u7b26\u4e32\u7684\u5f62\u5f0f\u50a8\u5b58\u8d77\u6765&#xff0c;\u50a8\u5b58\u5728\u7528\u6237\u7a7a\u95f4\u6808\u4e2d&#xff0c;\u4e0d\u662fPCB\u7684\u4e00\u90e8\u5206\u3002main\u51fd\u6570\u7684\u547d\u4ee4\u884c\u53c2\u6570\u8868&#xff0c;\u5c31\u662f\u6211\u4eec\u547d\u4ee4\u9009\u9879\u7684\u5b9e\u73b0\u539f\u7406&#xff0c;\u8f93\u5165\u7684\u9009\u9879\u4e0e\u547d\u4ee4\u884c\u53c2\u6570\u4e2d\u7684\u4f5c\u6bd4\u8f83&#xff0c;\u7ed9\u4e0d\u540c\u7684\u9009\u9879\u5b9e\u73b0\u4e0d\u540c\u7684\u529f\u80fd\u3002<\/p>\n<p>#include&lt;stdio.h&gt;<\/p>\n<p>#include &lt;string.h&gt;<br \/>\nint main(int argc,char* argv[])<br \/>\n{<br \/>\n        \/*<br \/>\n        for(int i &#061; 0; i&lt; argc;i&#043;&#043;)<br \/>\n        {<br \/>\n                printf(&#034;argv[%d]:%s\\\\n&#034;,i,argv[i]);<\/p>\n<p>        }<br \/>\n*\/<\/p>\n<p>if(strcmp(argv[1], &#034;a&#034;) &#061;&#061; 0)<br \/>\n{<br \/>\n    printf(&#034;\u8fd9\u662f\u529f\u80fd\u4e00\\\\n&#034;);<br \/>\n}<br \/>\nif(strcmp(argv[1], &#034;b&#034;) &#061;&#061; 0)<br \/>\n{<br \/>\n    printf(&#034;\u8fd9\u662f\u529f\u80fd\u4e8c\\\\n&#034;);<br \/>\n}<\/p>\n<p>        \/\/printf(&#034;It&#039;s pretty!\\\\n&#034;);<br \/>\n        return 0;<br \/>\n}<br \/>\n~                       <\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ gcc code.c -o code<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ .\/code a<br \/>\n\u8fd9\u662f\u529f\u80fd\u4e00<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ .\/code b<br \/>\n\u8fd9\u662f\u529f\u80fd\u4e8c<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ <\/p>\n<h2 style=\"background-color:transparent\">PATH<\/h2>\n<p>\u7cfb\u7edf\u7684\u547d\u4ee4\u548c\u6211\u4eec\u81ea\u5df1\u5199\u7684\u7a0b\u5e8f\u672c\u8d28\u4e0a\u90fd\u662f\u53ef\u6267\u884c\u7a0b\u5e8f&#xff0c;\u6ca1\u6709\u672c\u8d28\u4e0a\u7684\u533a\u522b&#xff0c;\u4e3a\u4ec0\u4e48\u6211\u4eec\u7684\u7a0b\u5e8f\u5728\u6267\u884c\u65f6\u8981\u52a0\u4e0a.\/\u800cls\u5374\u76f4\u63a5\u5199\u547d\u4ee4\u5c31\u884c\u5462&#xff1f;\u8981\u6267\u884c\u4e00\u4e2a\u7a0b\u5e8f&#xff0c;\u9996\u5148\u8981\u628a\u8fd9\u4e2a\u7a0b\u5e8f\u627e\u5230\u3002<\/p>\n<p>\u8fd8\u8bb0\u5f97.\/\u5206\u522b\u662f\u4ec0\u4e48\u5417&#xff0c;&#039;.&#039;\u662f\u5f53\u524d\u76ee\u5f55&#xff1b;&#039;\/&#039;\u662f\u76ee\u5f55\u5206\u5272\u7b26&#xff1b;\u8fde\u5728\u4e00\u8d77\u610f\u5473\u5728\u5f53\u524d\u76ee\u5f55\u5bfb\u627e\u53ef\u6267\u884c\u6587\u4ef6\u3002\u7cfb\u7edf\u81ea\u8eab\u7684\u547d\u4ee4\u7684\u5b9e\u73b0\u80af\u5b9a\u662f\u4e0d\u5728\u5f53\u524d\u76ee\u5f55\u7684&#xff0c;PATH\u8fd9\u4e2a\u73af\u5883\u53d8\u91cf\u4f1a\u544a\u8bc9<span style=\"background-color:#a2e043\">bash<\/span>\u53bb\u54ea\u627e\u8981\u6267\u884c\u7684\u547d\u4ee4\u7684\u53ef\u6267\u884c\u7a0b\u5e8f\u3002<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ echo $PATH<br \/>\n\/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ <\/p>\n<p>\u628a\u6211\u4eec\u81ea\u5df1\u7684\u547d\u4ee4\u4e5f\u52a0\u5230PATH\u4e2d&#xff0c;\u5c31\u53ef\u4ee5\u4e0d\u5e26.\/\u76f4\u63a5\u6267\u884c\u4e86\u3002<\/p>\n<h3 style=\"background-color:transparent\">\u73af\u5883\u53d8\u91cf\u8868&#xff08;\u73af\u5883\u53d8\u91cf\u5982\u4f55\u88ab\u5b58\u50a8&#xff09;<\/h3>\n<p>\u5f53\u7cfb\u7edf\u542f\u52a8\u65f6&#xff0c;bash\u4fbf\u4f1a\u62ff\u5230\u7cfb\u7edf\u4e2d\u7684\u73af\u5883\u53d8\u91cf&#xff0c;bash\u4f1a\u7ef4\u62a4\u4e00\u5f20\u73af\u5883\u53d8\u91cf\u8868\u6765\u5b58\u50a8\u73af\u5883\u53d8\u91cf\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" alt=\"\" height=\"510\" src=\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/01\/20260118035923-696c5a9bedbfc.png\" width=\"775\" \/><\/p>\n<p>\u73af\u5883\u53d8\u91cf\u8868\u5c31\u662f\u4e00\u4e2a\u6307\u9488\u6570\u7ec4&#xff0c;\u6309\u7167\u4e0b\u6807\u5c06\u73af\u5883\u53d8\u91cf\u50a8\u5b58\u5230\u6570\u7ec4\u4e2d\u3002bash\u4f1a\u7ef4\u62a4\u4e24\u5f20\u8868&#xff08;\u6682\u65f6\u53ea\u5b66\u5230\u8fd9\u4e24\u4e2a&#xff0c;\u5f53\u7136\u4e00\u5171\u4e0d\u6b62\u4e24\u4e2a&#xff09;&#xff0c;<span style=\"background-color:#a2e043\">\u73af\u5883\u53d8\u91cf\u8868\u548c\u547d\u4ee4\u884c\u53c2\u6570\u8868<\/span>&#xff0c;\u5f53\u6211\u4eec\u8f93\u5165<\/p>\n<p>ls -l -a<\/p>\n<p>\u65f6&#xff0c;bash\u4f1a\u5148\u62ff\u5230\u8fd9\u4e2a\u547d\u4ee4&#xff0c;\u7136\u540e\u5c06\u547d\u4ee4\u62c6\u5206\u4e4b\u540e\u5f62\u6210\u4e00\u5f20\u547d\u4ee4\u884c\u53c2\u6570\u8868&#xff0c;\u7136\u540e\u53bbPATH\u4e2d\u627e\u6709\u6ca1\u6709ls\u8fd9\u4e2a\u547d\u4ee4&#xff0c;\u5982\u679c\u6709\u547d\u4ee4\u5c31\u6267\u884c&#xff08;\u65b0\u5efa\u4e00\u4e2a\u5b50\u8fdb\u7a0b&#xff09;&#xff0c;\u6ca1\u6709\u5c31\u62a5\u9519\u3002<\/p>\n<h3 style=\"background-color:transparent\">\u4fee\u6539PATH<\/h3>\n<h4>\u5c06\u7a0b\u5e8f\u8def\u5f84\u6dfb\u52a0\u5230PATH<\/h4>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ PATH&#061;$PATH:\/home\/xian\/lession16<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ code<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ code a<br \/>\n\u8fd9\u662f\u529f\u80fd\u4e00<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ echo $PATH<br \/>\n\/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin:\/home\/xian\/lession16<\/p>\n<p>\u628a\u6211\u4eec\u7684\u7a0b\u5e8f\u76ee\u5f55\u6dfb\u52a0\u5230PATH\u4e4b\u540e&#xff0c;\u6211\u4eec\u6267\u884c\u6211\u4eec\u7684\u53ef\u6267\u884c\u7a0b\u5e8f\u5c31\u4e0d\u9700\u8981\u5728\u52a0\u4e0a.\/\u4e86\u3002\u6ce8\u610f\u4e0d\u8981\u518d\u7b49\u53f7\u524d\u540e\u52a0\u7a7a\u683c\u3002<\/p>\n<h4 style=\"background-color:transparent\">\u8986\u76d6PATH<\/h4>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ PATH&#061;\/home\/xian\/lession16<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ code b<br \/>\n\u8fd9\u662f\u529f\u80fd\u4e8c<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ ls -l<br \/>\nCommand &#039;ls&#039; is available in the following places<br \/>\n * \/bin\/ls<br \/>\n * \/usr\/bin\/ls<br \/>\nThe command could not be located because &#039;\/bin:\/usr\/bin&#039; is not included in the PATH environment variable.<br \/>\nls: command not found<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ <\/p>\n<p>\u76f4\u63a5\u5c06PATH\u8bbe\u7f6e\u4e3a\u5f53\u524d\u8def\u5f84&#xff0c;\u540c\u6837\u7684\u4e0d\u9700\u8981\u518d\u544a\u8bc9bash\u5728\u5f53\u524d\u76ee\u5f55\u4e0b\u627e\u6211\u4eec\u7684\u53ef\u6267\u884c\u7a0b\u5e8f&#xff0c;\u76f4\u63a5\u8fd0\u884c\u5373\u53ef\u3002\u4f46\u662f\u8fd9\u6837\u64cd\u4f5c\u7684\u8bdd&#xff0c;\u7531\u4e8ePATH\u88ab\u4fee\u6539\u4e86&#xff0c;\u6ca1\u6709\u4e86\u7cfb\u7edf\u547d\u4ee4\u7684\u8def\u5f84&#xff0c;bash\u627e\u4e0d\u5230\u7cfb\u7edf\u547d\u4ee4\u4e86&#xff0c;\u7cfb\u7edf\u547d\u4ee4\u5c31\u4e0d\u80fd\u4f7f\u7528\u4e86\u3002<\/p>\n<p><span style=\"background-color:#a2e043\">\u8fd9\u4e24\u79cd\u4fee\u6539\u73af\u5883\u53d8\u91cf\u7684\u65b9\u5f0f\u90fd\u53ea\u6709\u5728\u5f53\u524d\u7684\u7ec8\u7aef\u6709\u6548&#xff0c;\u9000\u51fa\u91cd\u65b0\u767b\u5f55\u540e&#xff0c;PATH\u53c8\u4f1a\u5237\u65b0\u3002<\/span><\/p>\n<h2>\u73af\u5883\u53d8\u91cf\u7684\u4ece\u54ea\u6765<\/h2>\n<p>bash\u4f1a\u7ef4\u62a4\u4e00\u4e2a\u73af\u5883\u53d8\u91cf\u8868&#xff0c;\u90a3\u4e48\u6700\u5f00\u59cb\u7684\u65f6\u5019bash\u662f\u4ece\u54ea\u91cc\u62ff\u5230\u7684\u73af\u5883\u53d8\u91cf\u5462&#xff1f;<\/p>\n<h3 style=\"background-color:transparent\">\u914d\u7f6e\u6587\u4ef6<\/h3>\n<p>\u5207\u6362\u5230\u5bb6\u76ee\u5f55&#xff0c;\u67e5\u770b\u76ee\u5f55\u4e0b\u7684\u6240\u6709\u6587\u4ef6&#xff0c;\u6211\u4eec\u4f1a\u53d1\u73b0\u6709\u4e00\u4e2a.bashrc\u3002<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~$ cd ~<br \/>\nxian&#064;VM-8-17-ubuntu:~$ ls -al<br \/>\ntotal 108<br \/>\ndrwxr-x&#8212; 15 xian xian  4096 Jan 13 22:40 .<br \/>\ndrwxr-xr-x  5 root root  4096 Sep 11 10:39 ..<br \/>\n-rw&#8212;&#8212;-  1 xian xian 11165 Jan 14 20:36 .bash_history<br \/>\n-rw-r&#8211;r&#8211;  1 xian xian   220 Mar 31  2024 .bash_logout<br \/>\n-rw-r&#8211;r&#8211;  1 xian xian  3771 Mar 31  2024 .bashrc<br \/>\ndrwx&#8212;&#8212;  3 xian xian  4096 Jan  3 22:54 .config<br \/>\n-rw-rw-r&#8211;  1 xian xian    47 Sep 11 22:29 .gitconfig<br \/>\n-rw&#8212;&#8212;-  1 xian xian    20 Jan 11 14:39 .lesshst<br \/>\ndrwxrwxr-x  5 xian xian  4096 Oct 29 23:29 lession1<br \/>\ndrwxrwxr-x  2 xian xian  4096 Nov 11 23:06 lession10<br \/>\ndrwxrwxr-x  2 xian xian  4096 Nov  8 16:16 lession1108<br \/>\ndrwxrwxr-x  2 xian xian  4096 Dec 13 22:28 lession12<br \/>\ndrwxrwxr-x  2 xian xian  4096 Dec 23 22:36 lession13<br \/>\ndrwxrwxr-x  2 xian xian  4096 Jan  5 15:30 lession14<br \/>\ndrwxrwxr-x  2 xian xian  4096 Jan 11 14:40 lession15<br \/>\ndrwxrwxr-x  2 xian xian  4096 Jan 13 22:40 lession16<br \/>\ndrwxrwxr-x  2 xian xian  4096 Sep 11 17:18 lession2<br \/>\ndrwxrwxr-x  2 xian xian  4096 Nov  5 22:06 lession8<br \/>\ndrwxrwxr-x  2 xian xian  4096 Nov  5 22:47 lession9<br \/>\ndrwxrwxr-x  3 xian xian  4096 Sep 13 23:39 .local<br \/>\n-rw-r&#8211;r&#8211;  1 xian xian   807 Mar 31  2024 .profile<br \/>\n-rw&#8212;&#8212;-  1 xian xian 14003 Jan 13 22:40 .viminfo<\/p>\n<p>\u5f53\u6211\u4eec\u767b\u5f55\u65f6&#xff0c;bash\u901a\u8fc7\u9605\u8bfb.bashrc\u548c.profile\u4e2d\u7684\u5185\u5bb9\u5c31\u80fd\u5c06\u73af\u5883\u53d8\u91cf\u914d\u7f6e\u51fa\u6765\u3002\u53ea\u8981\u5c06\u6211\u4eec\u7684\u7a0b\u5e8f\u7684\u8def\u5f84\u6dfb\u52a0\u5230\u914d\u7f6e\u6587\u4ef6\u4e2d&#xff0c;\u91cd\u542f\u4e5f\u4f1a\u4fdd\u5b58\u4e0b\u6765\u3002<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~$ vim .profile<\/p>\n<p>\u5728.bashrc\u7684\u672b\u5c3e\u52a0\u4e0a<\/p>\n<p>export PATH&#061;&#034;\/home\/xian\/lession16:$PATH&#034;<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~$ echo $PATH<br \/>\n\/home\/xian\/lession16:\/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin<br \/>\nxian&#064;VM-8-17-ubuntu:~$ code a<br \/>\n\u8fd9\u662f\u529f\u80fd\u4e00<br \/>\nxian&#064;VM-8-17-ubuntu:~$ <\/p>\n<p>\u91cd\u542f\u4e00\u6b21\u7ec8\u7aef&#xff0c;\u6211\u4eec\u7684\u7a0b\u5e8f\u5c31\u53ef\u4ee5\u6267\u884c\u76f4\u63a5\u6267\u884c\u4e86\u3002\u8fd9\u6837\u6216\u8bb8\u4e3a\u6211\u4eec\u63d0\u4f9b\u4e86\u6682\u65f6\u7684\u4fbf\u5229&#xff0c;\u4f46\u662fLinux\u4e2d\u7684\u547d\u4ee4\u90fd\u662f\u7ecf\u8fc7\u4e86\u6807\u51c6\u5316\u7684\u53d1\u5e03\u4e86\u6d41\u7a0b&#xff0c;\u7ecf\u8fc7\u4e86\u65e0\u6570\u6b21\u6d4b\u8bd5\u540e\u624d\u53d1\u5e03\u7684\u3002\u8fd9\u6837\u505a\u4f1a\u6709\u4ee5\u4e0b\u98ce\u9669&#xff1a;<\/p>\n<li>\n<p>\u547d\u4ee4\u6c61\u67d3\u98ce\u9669&#xff1a;Linux\u7cfb\u7edf\u4e2d\u7684\u6807\u51c6\u547d\u4ee4\u90fd\u7ecf\u8fc7\u4e86\u4e25\u683c\u7684\u6807\u51c6\u5316\u53d1\u5e03\u6d41\u7a0b\u548c\u65e0\u6570\u6b21\u6d4b\u8bd5\u3002\u800c\u6211\u4eec\u81ea\u5df1\u7f16\u5199\u7684\u7a0b\u5e8f\u53ef\u80fd\u5b58\u5728\u5404\u79cd\u672a\u53d1\u73b0\u7684\u9519\u8bef\u3002<\/p>\n<\/li>\n<li>\n<p>\u5b89\u5168\u9690\u60a3&#xff1a;\u5982\u679c\u6211\u4eec\u7684\u7a0b\u5e8f\u5b58\u5728\u5b89\u5168\u6f0f\u6d1e&#xff0c;\u53ef\u80fd\u4f1a\u88ab\u6076\u610f\u5229\u7528\u3002<\/p>\n<\/li>\n<li>\n<p>\u547d\u4ee4\u51b2\u7a81&#xff1a;\u5982\u679c\u6211\u4eec\u7684\u7a0b\u5e8f\u4e0e\u7cfb\u7edf\u547d\u4ee4\u540c\u540d&#xff0c;\u4f1a\u5bfc\u81f4\u7cfb\u7edf\u6807\u51c6\u547d\u4ee4\u88ab\u8986\u76d6\u3002<\/p>\n<\/li>\n<li>\n<p>\u7ef4\u62a4\u56f0\u96be&#xff1a;\u968f\u7740\u81ea\u5b9a\u4e49\u547d\u4ee4\u589e\u591a&#xff0c;PATH\u73af\u5883\u53d8\u91cf\u4f1a\u53d8\u5f97\u81c3\u80bf&#xff0c;\u589e\u52a0\u7cfb\u7edf\u7ef4\u62a4\u96be\u5ea6\u3002<\/p>\n<\/li>\n<h2>\u5176\u4ed6\u73af\u5883\u53d8\u91cf<\/h2>\n<h3>HOME<\/h3>\n<p>\nHOME\u662fLinux\/Unix\u7cfb\u7edf\u4e2d\u4e00\u4e2a\u91cd\u8981\u7684\u73af\u5883\u53d8\u91cf&#xff0c;\u5b83\u6307\u5411\u5f53\u524d\u7528\u6237\u7684\u5bb6\u76ee\u5f55&#xff08;\u4e3b\u76ee\u5f55&#xff09;\u3002\u6bcf\u4e2a\u7528\u6237\u767b\u5f55\u7cfb\u7edf\u540e\u90fd\u4f1a\u81ea\u52a8\u8bbe\u7f6e\u8fd9\u4e2a\u53d8\u91cf&#xff0c;\u901a\u5e38\u8def\u5f84\u4e3a\/home\/\u7528\u6237\u540d\u3002<\/p>\n<ul>\n<li>\n<p>\u4f7f\u7528\u793a\u4f8b&#xff1a;<\/p>\n<p>cd ~  # \u6ce2\u6d6a\u7ebf~\u4f1a\u88abshell\u81ea\u52a8\u66ff\u6362\u4e3a$HOME\u7684\u503c<br \/>\necho $HOME  # \u663e\u793a\u5f53\u524d\u7528\u6237\u7684\u5bb6\u76ee\u5f55\u8def\u5f84<\/p>\n<\/li>\n<li>\n<p>\u7279\u6b8a\u573a\u666f&#xff1a;<\/p>\n<ul>\n<li>root\u7528\u6237\u7684\u5bb6\u76ee\u5f55\u901a\u5e38\u662f\/root<\/li>\n<li>\u5728shell\u811a\u672c\u4e2d\u7ecf\u5e38\u7528$HOME\u6765\u5f15\u7528\u7528\u6237\u4e13\u5c5e\u76ee\u5f55<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3>HISTSIZE<\/h3>\n<p>\n\u8fd9\u4e2a\u73af\u5883\u53d8\u91cf\u63a7\u5236shell\u5386\u53f2\u8bb0\u5f55\u4fdd\u5b58\u7684\u547d\u4ee4\u6570\u91cf\u4e0a\u9650\u3002<\/p>\n<ul>\n<li>\u5178\u578b\u8bbe\u7f6e&#xff1a;\n<p>HISTSIZE&#061;1000  # \u9ed8\u8ba4\u503c\u901a\u5e38\u662f500\u62161000<\/p>\n<\/li>\n<li>\u6ce8\u610f\u4e8b\u9879&#xff1a;\n<ul>\n<li>\u8bbe\u7f6e\u8fc7\u5927\u4f1a\u5360\u7528\u5185\u5b58<\/li>\n<li>\u53ef\u901a\u8fc7history\u547d\u4ee4\u67e5\u770b\u4fdd\u5b58\u7684\u5386\u53f2\u547d\u4ee4<\/li>\n<li>\u4fee\u6539\u540e\u9700\u8981\u91cd\u65b0\u767b\u5f55\u6216\u6267\u884csource ~\/.bashrc\u751f\u6548<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3>LOGNAME\u548cUSER<\/h3>\n<p>\n\u8fd9\u4e24\u4e2a\u73af\u5883\u53d8\u91cf\u90fd\u8868\u793a\u5f53\u524d\u767b\u5f55\u7684\u7528\u6237\u540d\u3002<\/p>\n<ul>\n<li>\n<p>\u533a\u522b&#xff1a;<\/p>\n<ul>\n<li>LOGNAME\u662fPOSIX\u6807\u51c6\u53d8\u91cf<\/li>\n<li>USER\u662fBSD\u98ce\u683c\u53d8\u91cf<\/li>\n<li>\u5728\u5927\u591a\u6570\u73b0\u4ee3\u7cfb\u7edf\u4e2d\u4e24\u8005\u503c\u76f8\u540c<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<h3 style=\"background-color:transparent\">OLDPWD<br \/>\n\u8fd9\u4e2a\u73af\u5883\u53d8\u91cf\u4fdd\u5b58\u4e86\u4e0a\u4e00\u4e2a\u5de5\u4f5c\u76ee\u5f55\u7684\u8def\u5f84\u3002<\/h3>\n<ul>\n<li>\u5178\u578b\u7528\u6cd5&#xff1a;\n<p>cd &#8211;  # \u5207\u6362\u5230\u4e0a\u4e00\u4e2a\u76ee\u5f55&#xff0c;\u76f8\u5f53\u4e8ecd $OLDPWD<\/p>\n<\/li>\n<li>\u7279\u70b9&#xff1a;\n<ul>\n<li>\u7531shell\u81ea\u52a8\u7ef4\u62a4<\/li>\n<li>\u6267\u884ccd\u547d\u4ee4\u65f6\u4f1a\u81ea\u52a8\u66f4\u65b0<\/li>\n<li>\u53ef\u7528\u4e8e\u7f16\u5199\u76ee\u5f55\u5207\u6362\u76f8\u5173\u7684shell\u811a\u672c<\/li>\n<\/ul>\n<\/li>\n<\/ul>\n<p>\u6ce8\u610f&#xff1a;\u6240\u6709\u8fd9\u4e9b\u73af\u5883\u53d8\u91cf\u90fd\u53ef\u4ee5\u901a\u8fc7env\u6216printenv\u547d\u4ee4\u67e5\u770b\u5f53\u524d\u8bbe\u7f6e\u7684\u503c\u3002<\/p>\n<h2 style=\"background-color:transparent\">\u83b7\u53d6\u73af\u5883\u53d8\u91cf\u7684\u65b9\u6cd5<\/h2>\n<h3>export<\/h3>\n<p>export\u53ef\u4ee5\u6dfb\u52a0\u73af\u5883\u53d8\u91cf&#xff1a;<\/p>\n<p>export PETX&#061;12345689<\/p>\n<p>\u4f7f\u7528env\u67e5\u770b\u73af\u5883\u53d8\u91cf&#xff0c;\u6211\u4eec\u4f1a\u53d1\u73b0\u73af\u5883\u53d8\u91cf\u4e2d\u786e\u5b9e\u591a\u4e86\u4e00\u4e2aPETX\u3002<\/p>\n<p><img loading=\"lazy\" decoding=\"async\" alt=\"\" height=\"87\" src=\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/01\/20260118035924-696c5a9c24ad5.png\" width=\"208\" \/><\/p>\n<h3 style=\"background-color:transparent\">env<\/h3>\n<p>\u4f7f\u7528\u547d\u4ee4env\u6211\u4eec\u53ef\u4ee5\u67e5\u770b\u7cfb\u7edf\u4e2d\u7684\u6240\u6709\u73af\u5883\u53d8\u91cf\u3002<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ env<br \/>\nSHELL&#061;\/bin\/bash<br \/>\nPWD&#061;\/home\/xian\/lession16<br \/>\nLOGNAME&#061;xian<br \/>\nXDG_SESSION_TYPE&#061;tty<br \/>\nHOME&#061;\/home\/xian<br \/>\nLANG&#061;en_US.UTF-8<br \/>\nLS_COLORS&#061;rs&#061;0:di&#061;01;34:ln&#061;01;36:mh&#061;00:pi&#061;40;33:so&#061;01;35:do&#061;01;35:bd&#061;40;33;01:cd&#061;40;33;01:or&#061;40;31;01:mi&#061;00:su&#061;37;41:sg&#061;30;43:ca&#061;00:tw&#061;30;424;42:st&#061;37;44:ex&#061;01;32:*.tar&#061;01;31:*.tgz&#061;01;31:*.arc&#061;01;31:*.arj&#061;01;31:*.taz&#061;01;31:*.lha&#061;01;31:*.lz4&#061;01;31:*.lzh&#061;01;31:*.lzma&#061;01;31:*.tlz&#061;01.txz&#061;01;31:*.tzo&#061;01;31:*.t7z&#061;01;31:*.zip&#061;01;31:*.z&#061;01;31:*.dz&#061;01;31:*.gz&#061;01;31:*.lrz&#061;01;31:*.lz&#061;01;31:*.lzo&#061;01;31:*.xz&#061;01;31:*.zst&#061;01;31:*.t1;31:*.bz2&#061;01;31:*.bz&#061;01;31:*.tbz&#061;01;31:*.tbz2&#061;01;31:*.tz&#061;01;31:*.deb&#061;01;31:*.rpm&#061;01;31:*.jar&#061;01;31:*.war&#061;01;31:*.ear&#061;01;31:*.sar&#061;01;31:*.ra31:*.alz&#061;01;31:*.ace&#061;01;31:*.zoo&#061;01;31:*.cpio&#061;01;31:*.7z&#061;01;31:*.rz&#061;01;31:*.cab&#061;01;31:*.wim&#061;01;31:*.swm&#061;01;31:*.dwm&#061;01;31:*.esd&#061;01;31:*.avif5:*.jpg&#061;01;35:*.jpeg&#061;01;35:*.mjpg&#061;01;35:*.mjpeg&#061;01;35:*.gif&#061;01;35:*.bmp&#061;01;35:*.pbm&#061;01;35:*.pgm&#061;01;35:*.ppm&#061;01;35:*.tga&#061;01;35:*.xbm&#061;01;35:*.1;35:*.tif&#061;01;35:*.tiff&#061;01;35:*.png&#061;01;35:*.svg&#061;01;35:*.svgz&#061;01;35:*.mng&#061;01;35:*.pcx&#061;01;35:*.mov&#061;01;35:*.mpg&#061;01;35:*.mpeg&#061;01;35:*.m2v&#061;01;35:&#061;01;35:*.webm&#061;01;35:*.webp&#061;01;35:*.ogm&#061;01;35:*.mp4&#061;01;35:*.m4v&#061;01;35:*.mp4v&#061;01;35:*.vob&#061;01;35:*.qt&#061;01;35:*.nuv&#061;01;35:*.wmv&#061;01;35:*.asf&#061;01;35&#061;01;35:*.rmvb&#061;01;35:*.flc&#061;01;35:*.avi&#061;01;35:*.fli&#061;01;35:*.flv&#061;01;35:*.gl&#061;01;35:*.dl&#061;01;35:*.xcf&#061;01;35:*.xwd&#061;01;35:*.yuv&#061;01;35:*.cgm&#061;01;35:*.1;35:*.ogv&#061;01;35:*.ogx&#061;01;35:*.aac&#061;00;36:*.au&#061;00;36:*.flac&#061;00;36:*.m4a&#061;00;36:*.mid&#061;00;36:*.midi&#061;00;36:*.mka&#061;00;36:*.mp3&#061;00;36:*.mpc&#061;00;36:*.0;36:*.ra&#061;00;36:*.wav&#061;00;36:*.oga&#061;00;36:*.opus&#061;00;36:*.spx&#061;00;36:*.xspf&#061;00;36:*~&#061;00;90:*#&#061;00;90:*.bak&#061;00;90:*.crdownload&#061;00;90:*.dpkg-dist&#061;0*.dpkg-new&#061;00;90:*.dpkg-old&#061;00;90:*.dpkg-tmp&#061;00;90:*.old&#061;00;90:*.orig&#061;00;90:*.part&#061;00;90:*.rej&#061;00;90:*.rpmnew&#061;00;90:*.rpmorig&#061;00;90:*.rpmsav90:*.swp&#061;00;90:*.tmp&#061;00;90:*.ucf-dist&#061;00;90:*.ucf-new&#061;00;90:*.ucf-old&#061;00;90:<br \/>\nPROMPT_COMMAND&#061;history -a; history -a;<br \/>\nSSH_CONNECTION&#061;222.173.124.254 63265 10.2.8.17 22<br \/>\nLESSCLOSE&#061;\/usr\/bin\/lesspipe %s %s<br \/>\nXDG_SESSION_CLASS&#061;user<br \/>\nTERM&#061;xterm<br \/>\nLESSOPEN&#061;| \/usr\/bin\/lesspipe %s<br \/>\nUSER&#061;xian<br \/>\nDISPLAY&#061;localhost:10.0<br \/>\nSHLVL&#061;2<br \/>\nXDG_SESSION_ID&#061;242454<br \/>\nXDG_RUNTIME_DIR&#061;\/run\/user\/0<br \/>\nSSH_CLIENT&#061;222.173.124.254 63265 22<br \/>\nXDG_DATA_DIRS&#061;\/usr\/local\/share:\/usr\/share:\/var\/lib\/snapd\/desktop<br \/>\nPATH&#061;\/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin<br \/>\nDBUS_SESSION_BUS_ADDRESS&#061;unix:path&#061;\/run\/user\/0\/bus<br \/>\nMAIL&#061;\/var\/mail\/xian<br \/>\nSSH_TTY&#061;\/dev\/pts\/1<br \/>\nOLDPWD&#061;\/home\/xian<br \/>\n_&#061;\/usr\/bin\/env<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ <\/p>\n<h3 style=\"background-color:transparent\">unset<\/h3>\n<p>\u901a\u8fc7unset\u6211\u4eec\u53ef\u4ee5\u5220\u9664\u73af\u5883\u53d8\u91cf&#xff1a;<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ unset PETX<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ <\/p>\n<h3 style=\"background-color:transparent\">getenv<\/h3>\n<p>getenv\u662f\u4e00\u4e2ac\u8bed\u8a00\u5e93\u51fd\u6570&#xff0c;\u7528\u4e8e\u5728\u7a0b\u5e8f\u8fd0\u884c\u65f6\u83b7\u53d6\u64cd\u4f5c\u7cfb\u7edf\u7684\u73af\u5883\u53d8\u91cf\u503c\u3002\u51fd\u6570\u539f\u578b&#xff1a;<\/p>\n<p>char *getenv(const char *name);<\/p>\n<p>\u901a\u8fc7\u8fd9\u4e2a\u7cfb\u7edf\u8c03\u7528\u6211\u4eec\u53ef\u4ee5\u5b9e\u73b0\u4e00\u4e2a\u53ea\u6709\u81ea\u5df1\u624d\u80fd\u8c03\u7528\u7684\u7a0b\u5e8f\u3002<\/p>\n<p>#include &lt;stdio.h&gt;<br \/>\n#include &lt;stdlib.h&gt;<br \/>\n#include &lt;string.h&gt;<\/p>\n<p>\/\/ \u5e26\u73af\u5883\u53d8\u91cf\u53c2\u6570\u7684 main \u51fd\u6570<br \/>\nint main(int argc, char *argv[], char *env[]) {<br \/>\n    (void)argc;  \/\/ \u672a\u4f7f\u7528\u53c2\u6570&#xff0c;\u907f\u514d\u7f16\u8bd1\u8b66\u544a<br \/>\n    (void)argv;  \/\/ \u672a\u4f7f\u7528\u53c2\u6570&#xff0c;\u907f\u514d\u7f16\u8bd1\u8b66\u544a<br \/>\n    (void)env;   \/\/ \u672a\u4f7f\u7528\u53c2\u6570&#xff0c;\u907f\u514d\u7f16\u8bd1\u8b66\u544a<\/p>\n<p>    const char *who &#061; getenv(&#034;USER&#034;);<br \/>\n    if (who &#061;&#061; NULL)<br \/>\n        return 1;<\/p>\n<p>    if (strcmp(who, &#034;xian&#034;) &#061;&#061; 0) {<br \/>\n        printf(&#034;\u8fd9\u662f\u7a0b\u5e8f\u7684\u6b63\u5e38\u6267\u884c\u903b\u8f91!\\\\n&#034;);<br \/>\n    } else {<br \/>\n        printf(&#034;Only xian can do!\\\\n&#034;);<br \/>\n    }<\/p>\n<p>    return 0;<br \/>\n}        <\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ vim code1.c<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ gcc code1.c -o code1<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ .\/code1<br \/>\n\u8fd9\u662f\u7a0b\u5e8f\u7684\u6b63\u5e38\u6267\u884c\u903b\u8f91!<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ <\/p>\n<p><span style=\"background-color:#a2e043\">env(environ)\u5c31\u662f\u73af\u5883\u53d8\u91cf\u8868\u3002<\/span><\/p>\n<h2 style=\"background-color:transparent\">\u73af\u5883\u53d8\u91cf\u7684\u7279\u6027<\/h2>\n<p>\u73af\u5883\u53d8\u91cf\u662f\u53ef\u4ee5\u88ab\u5b50\u8fdb\u7a0b\u7ee7\u627f\u7684&#xff0c;\u800c\u6211\u4eec\u521b\u5efa\u7684\u6240\u6709\u8fdb\u7a0b\u90fd\u662fbash\u7684\u5b50\u8fdb\u7a0b&#xff0c;\u6240\u6709\u73af\u5883\u53d8\u91cf\u662f\u6709\u5168\u5c40\u7684\u7279\u6027\u7684\u3002<\/p>\n<h3 style=\"background-color:transparent\">\u672c\u5730\u53d8\u91cf<\/h3>\n<p>\u5728Bash\u547d\u4ee4\u884c\u4e2d\u53ef\u4ee5\u76f4\u63a5\u5b9a\u4e49\u53d8\u91cf&#xff0c;\u8fd9\u7c7b\u53d8\u91cf\u79f0\u4e3a\u672c\u5730\u53d8\u91cf&#xff1a;<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ i&#061;1<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$ echo $i<br \/>\n1<br \/>\nxian&#064;VM-8-17-ubuntu:~\/lession16$<\/p>\n<p>\u672c\u5730\u53d8\u91cf\u4ec5\u5728\u5f53\u524d\u7ec8\u7aef\u4f1a\u8bdd\u4e2d\u6709\u6548\u3002\u4f7f\u7528set\u547d\u4ee4\u53ef\u4ee5\u67e5\u770b\u6240\u6709\u672c\u5730\u53d8\u91cf\u548c\u73af\u5883\u53d8\u91cf\u3002\u901a\u8fc7export\u547d\u4ee4\u53ef\u4ee5\u5c06\u672c\u5730\u53d8\u91cf\u8f6c\u6362\u4e3a\u73af\u5883\u53d8\u91cf&#xff1a;<\/p>\n<p>xian&#064;VM-8-17-ubuntu:~\/lession16$ export i<\/p>\n<h3 style=\"background-color:transparent\">\u5185\u5efa\u547d\u4ee4<\/h3>\n<p>\u901a\u5e38\u60c5\u51b5\u4e0b&#xff0c;\u6211\u4eec\u6267\u884c\u7684\u547d\u4ee4\u90fd\u662f\u4f5c\u4e3a\u8fdb\u7a0b\u8fd0\u884c\u7684&#xff0c;\u4e14\u8fd9\u4e9b\u8fdb\u7a0b\u90fd\u662fbash\u8fdb\u7a0b\u7684\u5b50\u8fdb\u7a0b\u3002\u7136\u800c&#xff0c;\u5185\u5efa\u547d\u4ee4\u7684\u6267\u884c\u65b9\u5f0f\u4e0d\u540c&#xff1a;\u5b83\u4eec\u4e0d\u4f1a\u521b\u5efa\u65b0\u7684\u5b50\u8fdb\u7a0b&#xff0c;\u800c\u662f\u7531bash\u76f4\u63a5\u8c03\u7528\u76f8\u5e94\u7684\u51fd\u6570\u6216\u7cfb\u7edf\u8c03\u7528\u6765\u5b8c\u6210\u3002<\/p>\n<p>\u5f53\u6211\u4eec\u8986\u76d6PATH\u65f6&#xff0c;\u8fd9\u4e9b\u547d\u4ee4\u4f9d\u7136\u80fd\u591f\u6267\u884c&#xff0c;\u56e0\u4e3a\u5b83\u4eec\u5c31\u4e0d\u5728PATH\u4e2d&#xff0c;\u5b83\u4eec\u672c\u8eab\u5c31\u662fshell\u7684\u4e00\u90e8\u5206\u3002pwd\u5c31\u662f\u5185\u5efa\u547d\u4ee4\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"<p>\u5f15\u5165\u6211\u4eec\u5728\u547d\u4ee4\u884c\u4e2d\u6267\u884c\u5982\u4e0b\u547d\u4ee4&#xff1a;xianVM-8-17-ubuntu:~\/lession15$ echo $PATH<br \/>\n\/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin\u7cfb\u7edf\u4f1a\u8f93\u51fa\u4e00\u6bb5\u7531:\u9694\u5f00\u7684\u8def\u5f84\u3002\u8fd9\u5176\u5b9e\u5c31\u662f\u6211\u4eec\u6bcf\u5929\u90fd\u5728\u7528\u7684\u4e1c\u897f&#xff0c;\u53ea\u662f\u6211\u4eec\u5e76\u4e0d\u81ea\u77e5\u3002\u5f53\u6211\u4eec\u8f93\u5165ls&#xff0c;ps&#xff0c;gcc\u547d<\/p>\n","protected":false},"author":2,"featured_media":61694,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[58,43,44],"topic":[],"class_list":["post-61698","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-linux","tag-43","tag-44"],"yoast_head":"<!-- This site is optimized with the Yoast SEO plugin v20.3 - https:\/\/yoast.com\/wordpress\/plugins\/seo\/ -->\n<title>\u3010Linux\u3011\u73af\u5883\u53d8\u91cf - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.wsisp.com\/helps\/61698.html\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"og:description\" content=\"\u5f15\u5165\u6211\u4eec\u5728\u547d\u4ee4\u884c\u4e2d\u6267\u884c\u5982\u4e0b\u547d\u4ee4&#xff1a;xianVM-8-17-ubuntu:~\/lession15$ echo $PATH \/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin\u7cfb\u7edf\u4f1a\u8f93\u51fa\u4e00\u6bb5\u7531:\u9694\u5f00\u7684\u8def\u5f84\u3002\u8fd9\u5176\u5b9e\u5c31\u662f\u6211\u4eec\u6bcf\u5929\u90fd\u5728\u7528\u7684\u4e1c\u897f&#xff0c;\u53ea\u662f\u6211\u4eec\u5e76\u4e0d\u81ea\u77e5\u3002\u5f53\u6211\u4eec\u8f93\u5165ls&#xff0c;ps&#xff0c;gcc\u547d\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.wsisp.com\/helps\/61698.html\" \/>\n<meta property=\"og:site_name\" content=\"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\" \/>\n<meta property=\"article:published_time\" content=\"2026-01-18T03:59:25+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/01\/20260118035923-696c5a9ba9d4a.png\" \/>\n<meta name=\"author\" content=\"admin\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"\u4f5c\u8005\" \/>\n\t<meta name=\"twitter:data1\" content=\"admin\" \/>\n\t<meta name=\"twitter:label2\" content=\"\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4\" \/>\n\t<meta name=\"twitter:data2\" content=\"7 \u5206\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\/\/schema.org\",\"@graph\":[{\"@type\":\"WebPage\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/61698.html\",\"url\":\"https:\/\/www.wsisp.com\/helps\/61698.html\",\"name\":\"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\",\"isPartOf\":{\"@id\":\"https:\/\/www.wsisp.com\/helps\/#website\"},\"datePublished\":\"2026-01-18T03:59:25+00:00\",\"dateModified\":\"2026-01-18T03:59:25+00:00\",\"author\":{\"@id\":\"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41\"},\"breadcrumb\":{\"@id\":\"https:\/\/www.wsisp.com\/helps\/61698.html#breadcrumb\"},\"inLanguage\":\"zh-Hans\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\/\/www.wsisp.com\/helps\/61698.html\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/61698.html#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"\u9996\u9875\",\"item\":\"https:\/\/www.wsisp.com\/helps\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/#website\",\"url\":\"https:\/\/www.wsisp.com\/helps\/\",\"name\":\"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3\",\"description\":\"\u9999\u6e2f\u670d\u52a1\u5668_\u9999\u6e2f\u4e91\u670d\u52a1\u5668\u8d44\u8baf_\u670d\u52a1\u5668\u5e2e\u52a9\u6587\u6863_\u670d\u52a1\u5668\u6559\u7a0b\",\"potentialAction\":[{\"@type\":\"SearchAction\",\"target\":{\"@type\":\"EntryPoint\",\"urlTemplate\":\"https:\/\/www.wsisp.com\/helps\/?s={search_term_string}\"},\"query-input\":\"required name=search_term_string\"}],\"inLanguage\":\"zh-Hans\"},{\"@type\":\"Person\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41\",\"name\":\"admin\",\"image\":{\"@type\":\"ImageObject\",\"inLanguage\":\"zh-Hans\",\"@id\":\"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/image\/\",\"url\":\"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery\",\"contentUrl\":\"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery\",\"caption\":\"admin\"},\"sameAs\":[\"http:\/\/wp.wsisp.com\"],\"url\":\"https:\/\/www.wsisp.com\/helps\/author\/admin\"}]}<\/script>\n<!-- \/ Yoast SEO plugin. -->","yoast_head_json":{"title":"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","robots":{"index":"index","follow":"follow","max-snippet":"max-snippet:-1","max-image-preview":"max-image-preview:large","max-video-preview":"max-video-preview:-1"},"canonical":"https:\/\/www.wsisp.com\/helps\/61698.html","og_locale":"zh_CN","og_type":"article","og_title":"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","og_description":"\u5f15\u5165\u6211\u4eec\u5728\u547d\u4ee4\u884c\u4e2d\u6267\u884c\u5982\u4e0b\u547d\u4ee4&#xff1a;xianVM-8-17-ubuntu:~\/lession15$ echo $PATH \/usr\/local\/sbin:\/usr\/local\/bin:\/usr\/sbin:\/usr\/bin:\/sbin:\/bin:\/usr\/games:\/usr\/local\/games:\/snap\/bin\u7cfb\u7edf\u4f1a\u8f93\u51fa\u4e00\u6bb5\u7531:\u9694\u5f00\u7684\u8def\u5f84\u3002\u8fd9\u5176\u5b9e\u5c31\u662f\u6211\u4eec\u6bcf\u5929\u90fd\u5728\u7528\u7684\u4e1c\u897f&#xff0c;\u53ea\u662f\u6211\u4eec\u5e76\u4e0d\u81ea\u77e5\u3002\u5f53\u6211\u4eec\u8f93\u5165ls&#xff0c;ps&#xff0c;gcc\u547d","og_url":"https:\/\/www.wsisp.com\/helps\/61698.html","og_site_name":"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","article_published_time":"2026-01-18T03:59:25+00:00","og_image":[{"url":"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/01\/20260118035923-696c5a9ba9d4a.png"}],"author":"admin","twitter_card":"summary_large_image","twitter_misc":{"\u4f5c\u8005":"admin","\u9884\u8ba1\u9605\u8bfb\u65f6\u95f4":"7 \u5206"},"schema":{"@context":"https:\/\/schema.org","@graph":[{"@type":"WebPage","@id":"https:\/\/www.wsisp.com\/helps\/61698.html","url":"https:\/\/www.wsisp.com\/helps\/61698.html","name":"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","isPartOf":{"@id":"https:\/\/www.wsisp.com\/helps\/#website"},"datePublished":"2026-01-18T03:59:25+00:00","dateModified":"2026-01-18T03:59:25+00:00","author":{"@id":"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41"},"breadcrumb":{"@id":"https:\/\/www.wsisp.com\/helps\/61698.html#breadcrumb"},"inLanguage":"zh-Hans","potentialAction":[{"@type":"ReadAction","target":["https:\/\/www.wsisp.com\/helps\/61698.html"]}]},{"@type":"BreadcrumbList","@id":"https:\/\/www.wsisp.com\/helps\/61698.html#breadcrumb","itemListElement":[{"@type":"ListItem","position":1,"name":"\u9996\u9875","item":"https:\/\/www.wsisp.com\/helps"},{"@type":"ListItem","position":2,"name":"\u3010Linux\u3011\u73af\u5883\u53d8\u91cf"}]},{"@type":"WebSite","@id":"https:\/\/www.wsisp.com\/helps\/#website","url":"https:\/\/www.wsisp.com\/helps\/","name":"\u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3","description":"\u9999\u6e2f\u670d\u52a1\u5668_\u9999\u6e2f\u4e91\u670d\u52a1\u5668\u8d44\u8baf_\u670d\u52a1\u5668\u5e2e\u52a9\u6587\u6863_\u670d\u52a1\u5668\u6559\u7a0b","potentialAction":[{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https:\/\/www.wsisp.com\/helps\/?s={search_term_string}"},"query-input":"required name=search_term_string"}],"inLanguage":"zh-Hans"},{"@type":"Person","@id":"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/358e386c577a3ab51c4493330a20ad41","name":"admin","image":{"@type":"ImageObject","inLanguage":"zh-Hans","@id":"https:\/\/www.wsisp.com\/helps\/#\/schema\/person\/image\/","url":"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery","contentUrl":"https:\/\/gravatar.wp-china-yes.net\/avatar\/?s=96&d=mystery","caption":"admin"},"sameAs":["http:\/\/wp.wsisp.com"],"url":"https:\/\/www.wsisp.com\/helps\/author\/admin"}]}},"_links":{"self":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/posts\/61698","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/comments?post=61698"}],"version-history":[{"count":0,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/posts\/61698\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/media\/61694"}],"wp:attachment":[{"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/media?parent=61698"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/categories?post=61698"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/tags?post=61698"},{"taxonomy":"topic","embeddable":true,"href":"https:\/\/www.wsisp.com\/helps\/wp-json\/wp\/v2\/topic?post=61698"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}