{"id":586,"date":"2016-03-10T09:00:46","date_gmt":"2016-03-10T01:00:46","guid":{"rendered":"http:\/\/www.datarelab.com\/blog\/?p=586"},"modified":"2016-03-10T09:00:46","modified_gmt":"2016-03-10T01:00:46","slug":"linux%e4%b8%8bc%e8%af%ad%e8%a8%80%e7%9a%84%e8%b0%83%e8%af%95","status":"publish","type":"post","link":"https:\/\/www.datarelab.com\/blog\/Technical_literature\/586.html","title":{"rendered":"Linux\u4e0bC\u8bed\u8a00\u7684\u8c03\u8bd5"},"content":{"rendered":"

\u8c03\u8bd5\u662f\u6bcf\u4e2a\u7a0b\u5e8f\u5458\u90fd\u4f1a\u9762\u4e34\u7684\u95ee\u9898. \u5982\u4f55\u63d0\u9ad8\u7a0b\u5e8f\u5458\u7684\u8c03\u8bd5\u6548\u7387, \u66f4\u597d\u66f4\u5feb\u5730\u5b9a\u4f4d\u7a0b\u5e8f\u4e2d\u7684\u95ee\u9898\u4ece\u800c\u52a0\u5feb\u7a0b\u5e8f\u5f00\u53d1\u7684\u8fdb\u5ea6, \u662f\u5927\u5bb6\u5171\u540c\u9762\u5bf9\u7684\u95ee\u9898. \u53ef\u80fdWindows\u7528\u6237\u987a\u53e3\u5c31\u4f1a\u8bf4\u51fa:\u7528VC\u5457 \ud83d\ude42 , \u5b83\u63d0\u4f9b\u4e86\u8bbe\u7f6e\u65ad\u70b9, \u5355\u6b65\u8ddf\u8e2a\u7b49\u7684\u56fe\u5f62\u754c\u9762, \u4f7f\u8c03\u8bd5\u8d77\u6765\u76f4\u89c2\u6613\u7528. \u4f46Linux\u7528\u6237\u53ef\u80fd\u8981\u751f\u95f7\u6c14\u4e86 O:-) : \u96be\u9053\u6211\u4eecLinux\u7a0b\u5e8f\u5458\u5c31\u53ea\u80fd\u4f7f\u7528\u539f\u59cb\u7684\u8c03\u8bd5\u65b9\u6cd5, \u5728\u4ee3\u7801\u4e2d\u52a0\u5165printf\u4fe1\u606f\u5417?\u96be\u9053Linux\u4e0b\u5c31\u6ca1\u6709\u597d\u7684C\u8bed\u8a00\u8c03\u8bd5\u5de5\u5177\u5417?<\/p>\n

\u5f53\u7136\u4e0d\u662f\u4e86. GNU\u65e9\u5c31\u7ec4\u7ec7\u5f00\u53d1\u4e86\u4e00\u5957C\u8bed\u8a00\u7f16\u8bd1\u5668(Gcc)\u548c\u8c03\u8bd5\u5de5\u5177(Gdb). Gdb\u867d\u7136\u6ca1\u6709\u56fe\u5f62\u5316\u7684\u53cb\u597d\u754c\u9762, \u4f46\u662f\u5b83\u5f3a\u5927\u7684\u529f\u80fd\u4e5f\u8db3\u4ee5\u4e0e\u5fae\u8f6f\u7684VC\u5de5\u5177\u76f8\u5ab2\u7f8e, \u7ed9Linux\u7a0b\u5e8f\u5458\u5e26\u6765\u4e86\u798f\u97f3. \u4e0b\u9762\u901a\u8fc7\u4e00\u4e2a\u7b80\u5355\u7684\u4f8b\u5b50, \u6f14\u793a\u4e00\u4e0bGdb\u7684\u4f7f\u7528\u6d41\u7a0b:<\/p>\n

\u793a\u4f8b\u6587\u4ef6 demo.c \u7684\u6e90\u4ee3\u7801\u5982\u4e0b:<\/strong><\/p>\n

#include <stdio.h>\r\n\r\nint sum(int, int);\r\n\r\nint main()\r\n{\r\n    int result;\r\n    int a = 1, b = 2;\r\n    result = sum(a, b);\r\n    printf(\"%d + %d = %d\\n\", a, b, result);\r\n    return 0;\r\n}\r\n\r\nint sum(int a, int b)\r\n{\r\n    return a + b;\r\n}<\/pre>\n
\u7f16\u8bd1\u6e90\u6587\u4ef6, \u751f\u6210\u53ef\u6267\u884c\u6587\u4ef6:<\/strong><\/p>\n
$ gcc -g -Wall -o demo demo.c<\/span>
\n\u867d\u7136\u8fd9\u6bb5\u7a0b\u5e8f\u6ca1\u6709\u9519\u8bef, \u4f46\u8c03\u8bd5\u5b8c\u5168\u6b63\u786e\u7684\u7a0b\u5e8f\u53ef\u4ee5\u66f4\u52a0\u4e86\u89e3Gdb\u7684\u4f7f\u7528\u6d41\u7a0b. \u63a5\u4e0b\u6765\u5c31\u542f\u52a8Gdb\u8fdb\u884c\u8c03\u8bd5.<\/p>\n
\u6ce8\u610f:<\/strong><\/p>\n
Gdb\u8fdb\u884c\u8c03\u8bd5\u7684\u662f\u53ef\u6267\u884c\u6587\u4ef6, \u800c\u4e0d\u662f\u201d.c\u201d\u6e90\u6587\u4ef6, \u56e0\u6b64, \u9700\u8981\u5148\u901a\u8fc7Gcc\u7f16\u8bd1\u751f\u6210\u53ef\u6267\u884c\u6587\u4ef6\u624d\u80fd\u7528Gdb\u8fdb\u884c\u8c03\u8bd5.<\/em><\/span>
\n\u4e00\u5b9a\u8981\u52a0\u4e0a\u9009\u9879\u201d-g\u201d, \u8fd9\u6837\u7f16\u8bd1\u51fa\u7684\u53ef\u6267\u884c\u4ee3\u7801\u4e2d\u624d\u5305\u542b\u8c03\u8bd5\u4fe1\u606f, \u5426\u5219Gdb\u65e0\u6cd5\u8f7d\u5165\u8be5\u53ef\u6267\u884c\u6587\u4ef6.<\/em><\/span>
\n\u4e0d\u80fd\u4f7f\u7528 -O2\u9009\u9879\u5bf9\u53ef\u6267\u884c\u6587\u4ef6\u8fdb\u884c\u4f18\u5316, \u56e0\u4e3a\u4f18\u5316\u4e4b\u540e\u53ef\u6267\u884c\u6587\u4ef6\u91cc\u7684\u7b26\u53f7\u8868\u4fe1\u606f\u5c06\u88ab\u5220\u9664, \u8fd9\u6837Gdb\u5c31\u65e0\u6cd5\u627e\u5230\u4f7f\u53ef\u6267\u884c\u6587\u4ef6\u4e0e\u6e90\u6587\u4ef6\u4e4b\u95f4\u7684\u5173\u8054\u4e86, \u4e5f\u5c31\u4e0d\u80fd\u8c03\u8bd5\u4e86.<\/em><\/span><\/p>\n
(1) \u542f\u52a8Gdb<\/strong><\/p>\n
$ gdb demo<\/span>
\nGNU gdb (GDB) 7.0-debian
\nCopyright (C) 2009 Free Software Foundation, Inc.
\nLicense GPLv3+: GNU GPL version 3 or later <http:\/\/gnu.org\/licenses\/gpl.html>
\nThis is free software: you are free to change and redistribute it.
\nThere is NO WARRANTY, to the extent permitted by law. Type \"show copying\"
\nand \"show warranty\" for details.
\nThis GDB was configured as \"x86_64-linux-gnu\".
\nFor bug reporting instructions, please see:
\n<http:\/\/www.gnu.org\/software\/gdb\/bugs\/>...
\nReading symbols from \/home\/wangsheng\/tmp\/demo\/gdb\/demo...done.
\n\u53ef\u4ee5\u770b\u51fa, \u5728Gdb\u7684\u542f\u52a8\u753b\u9762\u4e2d\u6307\u51fa\u4e86Gdb\u7684\u7248\u672c\u53f7, \u4f7f\u7528\u7684\u5e93\u6587\u4ef6\u7b49\u5934\u4fe1\u606f, \u63a5\u4e0b\u6765\u5c31\u8fdb\u5165\u4e86\u7531\u201d(gdb)\u201d\u5f00\u5934\u7684\u547d\u4ee4\u884c\u754c\u9762\u4e86.<\/p>\n
(2) \u67e5\u770b\u6e90\u6587\u4ef6<\/strong><\/p>\n
\u5728Gdb\u4e2d\u952e\u5165\u201dl\u201d(list\u7684\u7f29\u5199)\u53ef\u4ee5\u67e5\u770b\u6240\u8f7d\u5165\u7684\u6587\u4ef6, \u5982\u4e0b\u6240\u793a:<\/p>\n
(gdb) l
\n1 #include
\n2
\n3 int sum(int, int);
\n4
\n5 int
\n6 main()
\n7 {
\n8 int result;
\n9 int a = 1, b = 2;
\n10 result = sum(a, b);
\n(gdb) l
\n11 printf(\"%d + %d = %d\\n\", a, b, result);
\n12 return 0;
\n13 }
\n14
\n15 int
\n16 sum(int a, int b)
\n17 {
\n18 return a + b;
\n19 }
\n(gdb) l
\nLine number 20 out of range; demo.c has 19 lines.
\n\u53ef\u4ee5\u770b\u51fa, Gdb\u5217\u51fa\u7684\u6e90\u4ee3\u7801\u4e2d\u660e\u786e\u5730\u7ed9\u51fa\u4e86\u5bf9\u5e94\u7684\u884c\u53f7, \u8fd9\u6837\u5c31\u53ef\u4ee5\u5927\u5927\u5730\u65b9\u4fbf\u4ee3\u7801\u7684\u5b9a\u4f4d.<\/p>\n
(3) \u8bbe\u7f6e\u65ad\u70b9<\/strong><\/p>\n
\u8bbe\u7f6e\u65ad\u70b9\u662f\u8c03\u8bd5\u7a0b\u5e8f\u4e2d\u4e00\u4e2a\u975e\u5e38\u91cd\u8981\u7684\u624b\u6bb5, \u5b83\u53ef\u4ee5\u4f7f\u7a0b\u5e8f\u5230\u4e00\u5b9a\u4f4d\u7f6e\u6682\u505c\u8fd0\u884c. \u56e0\u6b64,\u53ef\u4ee5\u5728\u8be5\u4f4d\u7f6e\u65b9\u4fbf\u5730\u67e5\u770b\u53d8\u91cf\u7684\u503c, \u5806\u6808\u60c5\u51b5\u7b49, \u4ece\u800c\u627e\u51fa\u4ee3\u7801\u7684\u75c7\u7ed3\u6240\u5728.<\/p>\n
\u5728Gdb\u4e2d\u8bbe\u7f6e\u65ad\u70b9\u975e\u5e38\u7b80\u5355, \u53ea\u9700\u5728\u201db\u201d\u540e\u52a0\u5165\u5bf9\u5e94\u7684\u884c\u53f7\u5373\u53ef(\u8fd9\u662f\u6700\u5e38\u7528\u7684\u65b9\u5f0f). \u5982\u4e0b\u6240\u793a:<\/p>\n
(gdb) b 9
\nBreakpoint 2 at 0x4004f4: file demo.c, line 9.
\n\u6ce8\u610f: \u8be5\u65ad\u70b9\u7684\u4f5c\u7528\u662f\u5f53\u7a0b\u5e8f\u8fd0\u884c\u5230\u7b2c 9 \u884c\u65f6\u6682\u505c(\u7b2c 8 \u884c\u6267\u884c\u5b8c\u6bd5, \u7b2c 9 \u884c\u672a\u6267\u884c)<\/p>\n
(4) \u67e5\u770b\u65ad\u70b9\u4fe1\u606f<\/strong><\/p>\n
(gdb) info b
\nNum Type Disp Enb Address What
\n2 breakpoint keep y 0x00000000004004f4 in main at demo.c:9<\/p>\n
(5) \u8fd0\u884c\u4ee3\u7801<\/strong><\/p>\n
\u63a5\u4e0b\u6765\u5c31\u53ef\u8fd0\u884c\u4ee3\u7801\u4e86, Gdb\u9ed8\u8ba4\u4ece\u9996\u884c\u5f00\u59cb\u8fd0\u884c\u4ee3\u7801, \u53ef\u952e\u5165\u201dr\u201d(run\u7684\u7f29\u5199)\u5373\u53ef. \u82e5\u60f3\u4ece\u7a0b\u5e8f\u4e2d\u6307\u5b9a\u7684\u884c\u5f00\u59cb\u8fd0\u884c, \u53ef\u5728r\u540e\u9762\u52a0\u4e0a\u884c\u53f7.<\/p>\n
(gdb) r
\nStarting program: \/home\/wangsheng\/tmp\/demo\/gdb\/demo<\/p>\n
Breakpoint 2, main () at demo.c:9
\n9 int a = 1, b = 2;
\n\u53ef\u4ee5\u770b\u5230\u7a0b\u5e8f\u8fd0\u884c\u5230\u65ad\u70b9\u5904\u5c31\u505c\u6b62\u4e86.<\/p>\n
(6) \u67e5\u770b\u53d8\u91cf\u503c<\/strong><\/p>\n
\u952e\u5165p(print\u7684\u7f29\u5199)+\u53d8\u91cf\u540d\u5373\u53ef\u67e5\u770b\u8be5\u53d8\u91cf\u5728\u6b64\u65f6\u7684\u503c<\/p>\n
(gdb) p a
\n$1 = 1
\n(gdb) p b
\n$2 = 2
\n(gdb) p result
\n$3 = 32767
\n\u6ce8\u610f: \u8fd9\u91cc\u4e4b\u6240\u4ee5result\u662f\u4e00\u4e2a\u83ab\u540d\u5176\u5999\u7684\u503c, \u662f\u56e0\u4e3a\u58f0\u660eresult\u662f\u6ca1\u6709\u521d\u59cb\u5316, \u5176\u503c\u662f\u4e0d\u56fa\u5b9a\u7684\u3002<\/p>\n
(7) \u5355\u6b65\u6267\u884c<\/strong><\/p>\n
\u5355\u6b65\u8fd0\u884c\u53ef\u4ee5\u4f7f\u7528n(next\u7684\u7f29\u5199)\u6216\u8005s(step\u7684\u7f29\u5199), \u5b83\u4eec\u4e4b\u95f4\u7684\u533a\u522b\u5728\u4e8e: \u82e5\u6709\u51fd\u6570\u8c03\u7528\u7684\u65f6\u5019, s\u4f1a\u8fdb\u5165\u8be5\u51fd\u6570\u800cn\u4e0d\u4f1a. \u56e0\u6b64, s\u5c31\u7c7b\u4f3c\u4e8eVC\u7b49\u5de5\u5177\u4e2d\u7684\u201dstep in\u201d, n\u5c31\u7c7b\u4f3c\u4e8eVC\u7b49\u5de5\u5177\u4e2d\u7684\u201dstep over\u201d.<\/p>\n
\u5982\u679c\u4f7f\u7528n\u547d\u4ee4\u663e\u793a\u5982\u4e0b:<\/p>\n
(gdb) n
\n10 result = sum(a, b);
\n\u4e0b\u9762\u4f7f\u7528 s \u547d\u4ee4\uff0c\u8ddf\u8e2a\u8fdb\u5165 sum \u51fd\u6570:<\/p>\n
(gdb) s
\nsum (a=1, b=2) at demo.c:18
\n18 return a + b;
\n\u53ef\u4ee5\u770b\u51fa\u6267\u884c s \u547d\u4ee4\u65f6\u8fdb\u5165\u4e86sum\u51fd\u6570\u5185\u90e8, \u5982\u679c\u7528 n \u547d\u4ee4\u5219\u8df3\u8fc7\u51fd\u6570\u7684\u8c03\u7528\u90e8\u5206<\/span><\/em><\/p>\n
(8) \u6062\u590d\u7a0b\u5e8f\u8fd0\u884c<\/strong><\/p>\n
\u5728\u67e5\u770b\u53d8\u91cf\u503c\u4ee5\u53ca\u5806\u6808\u4e4b\u540e, \u5c31\u53ef\u4ee5\u4f7f\u7528\u547d\u4ee4c(continue)\u6062\u590d\u7a0b\u5e8f\u7684\u6b63\u5e38\u8fd0\u884c\u4e86. \u8fd9\u65f6, \u5b83\u4f1a\u628a\u5269\u4f59\u8fd8\u672a\u6267\u884c\u7684\u7a0b\u5e8f\u6267\u884c\u5b8c, \u5e76\u663e\u793a\u5269\u4f59\u7a0b\u5e8f\u7684\u6267\u884c\u7ed3\u679c.<\/p>\n
(gdb) c
\nContinuing.
\n1 + 2 = 3<\/p>\n
Program exited normally.
\n\u53ef\u4ee5\u770b\u51fa, \u7a0b\u5e8f\u5728\u8fd0\u884c\u5b8c\u540e\u9000\u51fa, \u4e4b\u540e\u7a0b\u5e8f\u5904\u4e8e\u201d\u505c\u6b62\u72b6\u6001\u201d.
\n\u8bf4\u660e: \u5728Gdb\u4e2d, \u7a0b\u5e8f\u7684\u8fd0\u884c\u72b6\u6001\u6709\u201d\u8fd0\u884c\u201d,\u201d\u6682\u505c\u201d\u548c\u201d\u505c\u6b62\u201d3\u79cd. \u5176\u4e2d\u201d\u6682\u505c\u201d\u72b6\u6001\u662f\u7a0b\u5e8f\u9047\u5230\u4e86\u65ad\u70b9\u6216\u8005\u89c2\u5bdf\u70b9, \u7a0b\u5e8f\u6682\u65f6\u505c\u6b62\u8fd0\u884c, \u800c\u6b64\u65f6\u51fd\u6570\u7684\u5730\u5740, \u51fd\u6570\u53c2\u6570, \u51fd\u6570\u5185\u7684\u5c40\u90e8\u53d8\u91cf\u90fd\u4f1a\u88ab\u538b\u5165\u201d\u6808(Stack)\u4e2d. \u6545\u5728\u8fd9\u79cd\u72b6\u6001\u4e0b\u53ef\u4ee5\u67e5\u770b\u51fd\u6570\u7684\u53d8\u91cf\u503c\u7b49\u5404\u79cd\u5c5e\u6027. \u4f46\u5728\u51fd\u6570\u5904\u4e8e\u201d\u505c\u6b62\u201d\u72b6\u6001\u4e4b\u540e, \u201c\u6808\u201d\u5c31\u4f1a\u81ea\u52a8\u64a4\u9500, \u5b83\u4e5f\u5c31\u65e0\u6cd5\u67e5\u770b\u5404\u79cd\u4fe1\u606f\u4e86<\/p>\n
\u5173\u4e8eGdb\u7684\u66f4\u591a\u547d\u4ee4, \u4f60\u53ef\u4ee5\u5728\u542f\u7528Gdb\u540e, \u8f93\u5165help\u547d\u4ee4\u67e5\u770b.<\/p>\n","protected":false},"excerpt":{"rendered":"
\u8c03\u8bd5\u662f\u6bcf\u4e2a\u7a0b\u5e8f\u5458\u90fd\u4f1a\u9762\u4e34\u7684\u95ee\u9898. \u5982\u4f55\u63d0\u9ad8\u7a0b\u5e8f\u5458\u7684\u8c03\u8bd5\u6548\u7387, \u66f4\u597d\u66f4\u5feb\u5730\u5b9a\u4f4d\u7a0b\u5e8f\u4e2d\u7684\u95ee\u9898\u4ece\u800c\u52a0\u5feb\u7a0b\u5e8f\u5f00\u53d1\u7684\u8fdb\u5ea6 […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-586","post","type-post","status-publish","format-standard","hentry","category-Technical_literature"],"views":2035,"_links":{"self":[{"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/posts\/586","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/comments?post=586"}],"version-history":[{"count":0,"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/posts\/586\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/media?parent=586"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/categories?post=586"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.datarelab.com\/blog\/wp-json\/wp\/v2\/tags?post=586"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}