📄 readdir.html
字号:
<!DOCTYPE HTML PUBLIC "-//W3O//DTD W3 HTML 2.0//EN"><!-- This collection of hypertext pages is Copyright 1995-2005 by Steve Summit. --><!-- Content from the book "C Programming FAQs: Frequently Asked Questions" --><!-- (Addison-Wesley, 1995, ISBN 0-201-84519-9) is made available here by --><!-- permission of the author and the publisher as a service to the community. --><!-- It is intended to complement the use of the published text --><!-- and is protected by international copyright laws. --><!-- The on-line content may be accessed freely for personal use --><!-- but may not be published or retransmitted without explicit permission. --><!-- --><!-- this page built Sat Dec 24 21:47:47 2005 by faqproc version 2.7 --><!-- from source file osdepfile.sgml dated Sat Jun 26 20:52:13 2004 --><!-- corresponding to FAQ list version 4.0 --><html><!-- Mirrored from c-faq.com/osdep/readdir.html by HTTrack Website Copier/3.x [XR&CO'2008], Sat, 14 Mar 2009 07:59:03 GMT --><head><meta name=GENERATOR content="faqproc"><title>Question 19.20</title><link href="diskfree.html" rev=precedes><link href="mkdir.html" rel=precedes><link href="index.html" rev=subdocument></head><body bgcolor="#ffffff"><a href="diskfree.html" rev=precedes><img src="../images/buttonleft.gif" alt="prev"></a><a href="index.html" rev=subdocument><img src="../images/buttonup.gif" alt="up"></a><a href="mkdir.html" rel=precedes><img src="../images/buttonright.gif" alt="next"></a> <a href="../index-2.html"><img src="../images/buttontop.gif" alt="top/contents"></a><a href="../search.html"><img src="../images/buttonsrch.gif" alt="search"></a><hr><p><!-- qbegin --><h1>comp.lang.c FAQ list<font color=blue>·</font><!-- qtag -->Question 19.20</h1><p><font face=Helvetica size=8 color=blue><b>Q:</b></font>How can I read a directory in a C program?</p><p><hr><p><font face=Helvetica size=8 color=blue><b>A:</b></font>See if you can usethe<TT>opendir</TT> and <TT>readdir</TT>functions,which arepart of the POSIX standardand areavailable on mostUnixvariants.Implementations also exist forMS-DOS,VMS,and other systems.(MS-DOS also hasFINDFIRST and FINDNEXTroutineswhich doessentially the same thing,andMS Windows has<TT>FindFirstFile</TT> and <TT>FindNextFile</TT>.)<TT>readdir</TT>returns just thefile names;if you need more information about the file,try calling <TT>stat</TT>.To match filenames to some wildcard pattern,see question <a href="../lib/regex.html">13.7</a>.</p><p>Here is a tiny example which lists the files in the current directory:<pre>#include <stdio.h>#include <sys/types.h>#include <dirent.h>main(){ struct dirent *dp; DIR *dfd = opendir("."); if(dfd != NULL) { while((dp = readdir(dfd)) != NULL) printf("%s\n", dp->d_name); closedir(dfd); } return 0;}</pre>(On older systems, the header file to <TT>#include</TT> may be <TT><direct.h></TT> or <TT><dir.h></TT>,and the pointer returned by <TT>readdir</TT> may be a <TT>struct direct *</TT>.This example assumes that <TT>"."</TT> is a synonym for the current directory.)</p><p>In a pinch, you could use<TT>popen</TT>(see question <a href="popen.html">19.30</a>)to call an operating system list-directory program,and read its output.(If you only need the filenames displayed to the user,you could conceivably use <TT>system</TT>;see question <a href="system.html">19.27</a>.)</p><p>References:K&R2 Sec. 8.6 pp. 179-184<br>PCS Sec. 13 pp. 230-1<br>POSIX Sec. 5.1<br>Schumacher, ed., <I>Software Solutions in C</I> Sec. 8<br></p><!-- aend --><p><hr><a href="diskfree.html" rev=precedes><img src="../images/buttonleft.gif" alt="prev"></a><a href="index.html" rev=subdocument><img src="../images/buttonup.gif" alt="up"></a><a href="mkdir.html" rel=precedes><img src="../images/buttonright.gif" alt="next"></a> <a href="../questions.html"><img src="../images/buttontop.gif" alt="contents"></a><a href="../search.html"><img src="../images/buttonsrch.gif" alt="search"></a><br><!-- lastfooter --><a href="../about.html">about this FAQ list</a> <a href="../eskimo.html">about eskimo</a> <a href="../search.html">search</a> <a href="../feedback.html">feedback</a> <a href="copyright.html">copyright</a><p>Hosted by<a href="http://www.eskimo.com/"><img src="../../www.eskimo.com/img/link/eskitiny.gif" alt="Eskimo North"></a></body><!-- Mirrored from c-faq.com/osdep/readdir.html by HTTrack Website Copier/3.x [XR&CO'2008], Sat, 14 Mar 2009 07:59:03 GMT --></html>⌨️ 快捷键说明
复制代码
Ctrl + C
搜索代码
Ctrl + F
全屏模式
F11
切换主题
Ctrl + Shift + D
显示快捷键
?
增大字号
Ctrl + =
减小字号
Ctrl + -