546 lines
24 KiB
HTML
546 lines
24 KiB
HTML
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN">
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<html>
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<head>
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<meta http-equiv="content-type" content="text/html; charset=iso-8859-1">
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<title>Debian Tutorial (Obsolete Documentation) - Text tools</title>
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<link href="index.html" rel="start">
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<link href="ch-X.html" rel="prev">
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<link href="ch-file_tools.html" rel="next">
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<link href="index.html#contents" rel="contents">
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<link href="index.html#copyright" rel="copyright">
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<link href="ch-about.html" rel="chapter" title="1 About this manual">
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<link href="ch-introduction.html" rel="chapter" title="2 Introduction">
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<link href="ch-start.html" rel="chapter" title="3 Getting started">
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<link href="ch-basics.html" rel="chapter" title="4 The Basics">
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<link href="ch-docs.html" rel="chapter" title="5 Reading documentation and getting help">
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<link href="ch-shell.html" rel="chapter" title="6 Using the shell">
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<link href="ch-files.html" rel="chapter" title="7 More on files">
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<link href="ch-editor.html" rel="chapter" title="8 Creating and editing text files">
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<link href="ch-custom_shell.html" rel="chapter" title="9 Customizing the shell">
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<link href="ch-X.html" rel="chapter" title="10 The X Window System">
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<link href="ch-text_tools.html" rel="chapter" title="11 Text tools">
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<link href="ch-file_tools.html" rel="chapter" title="12 File tools">
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<link href="ch-disks.html" rel="chapter" title="13 Using disks">
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<link href="ch-dpkg.html" rel="chapter" title="14 Removing and installing software">
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<link href="ch-troubleshooting.html" rel="chapter" title="15 Troubleshooting">
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<link href="ch-advanced.html" rel="chapter" title="16 Advanced topics">
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<link href="ch-next.html" rel="chapter" title="17 Where to from here?">
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<link href="ch-helping.html" rel="chapter" title="18 Contributing to Debian: How can I help?">
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<link href="ap-apps_appendix.html" rel="appendix" title="A A brief survey of available applications">
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<link href="ap-components_appendix.html" rel="appendix" title="B Summary of GNU/Linux system components">
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<link href="ap-booting_appendix.html" rel="appendix" title="C Appendix C: Booting the system">
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<link href="ap-misc_appendix.html" rel="appendix" title="D Miscellaneous">
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<link href="ch-about.html#s-acknowldgements" rel="section" title="1.1 Acknowledgements">
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<link href="ch-introduction.html#s-introduction-debian" rel="section" title="2.1 What is Debian?">
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<link href="ch-introduction.html#s-introduction-DFSG" rel="section" title="2.2 What's free software?">
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<link href="ch-introduction.html#s-introduction-how" rel="section" title="2.3 How to Read This Book">
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<link href="ch-introduction.html#s-introduction-ldp" rel="section" title="2.4 The Linux Documentation Project">
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<link href="ch-start.html#s-start-multi" rel="section" title="3.1 A multiuser, multitasking operating system">
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<link href="ch-start.html#s-start-login" rel="section" title="3.2 Logging in">
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<link href="ch-start.html#s-start-keys" rel="section" title="3.3 Keys">
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<link href="ch-start.html#s-start-commandline" rel="section" title="3.4 Command history and editing the command line">
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<link href="ch-start.html#s-start-root" rel="section" title="3.5 Logging in as root">
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<link href="ch-start.html#s-start-VC" rel="section" title="3.6 Virtual consoles">
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<link href="ch-start.html#s-start-shutdown" rel="section" title="3.7 Shutting down">
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<link href="ch-basics.html#s-basics-commandline" rel="section" title="4.1 The command line and <samp>man</samp> pages">
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<link href="ch-basics.html#s-basics-files" rel="section" title="4.2 Files and Directories">
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<link href="ch-basics.html#s-basics-processes" rel="section" title="4.3 Processes">
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<link href="ch-basics.html#s-basics-shell" rel="section" title="4.4 The shell">
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<link href="ch-basics.html#s-basics-jobs" rel="section" title="4.5 Managing processes with Bash">
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<link href="ch-basics.html#s-basics-bash" rel="section" title="4.6 A few Bash features">
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<link href="ch-basics.html#s-basics-identity" rel="section" title="4.7 Managing your identity">
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<link href="ch-docs.html#s-docs-sources" rel="section" title="5.1 Kinds of documentation">
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<link href="ch-docs.html#s-docs-info" rel="section" title="5.2 Using info">
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<link href="ch-docs.html#s-docs-textfiles" rel="section" title="5.3 Viewing text files with more and less">
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<link href="ch-docs.html#s-docs-howtos" rel="section" title="5.4 HOWTOs">
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<link href="ch-docs.html#s-docs-support" rel="section" title="5.5 Getting help from a person">
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<link href="ch-docs.html#s-docs-sysinfo" rel="section" title="5.6 Getting information from the system">
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<link href="ch-shell.html#s-shell-variables" rel="section" title="6.1 Environment variables">
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<link href="ch-shell.html#s-shell-path" rel="section" title="6.2 Where commands live: the <samp>PATH</samp> variable">
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<link href="ch-shell.html#s-custom_shell-aliases" rel="section" title="6.3 Aliases and shell functions">
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<link href="ch-shell.html#s-shell-io" rel="section" title="6.4 Controlling input and output">
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<link href="ch-shell.html#s-shell-modifiers" rel="section" title="6.5 Specifying how and when to run commands">
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<link href="ch-shell.html#s-shell-wildcards" rel="section" title="6.6 Filename expansion ("Wildcards")">
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<link href="ch-shell.html#s6.7" rel="section" title="6.7 Interactive/non-interactive">
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<link href="ch-files.html#s-files-permissions" rel="section" title="7.1 Permissions">
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<link href="ch-files.html#s-files-tour" rel="section" title="7.2 What files are on my system? Where can I put my own files?">
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<link href="ch-files.html#s-file-manager" rel="section" title="7.3 Using a filemanager">
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<link href="ch-editor.html#s-editor-textfile" rel="section" title="8.1 What's a text file?">
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<link href="ch-editor.html#s-editor-editor" rel="section" title="8.2 Text editors">
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<link href="ch-editor.html#s-editor-vi" rel="section" title="8.3 Creating and editing a text file with <code>vi</code>">
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<link href="ch-custom_shell.html#s-custom_shell-dotfiles" rel="section" title="9.1 .rc files and <samp>ls -a</samp>">
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<link href="ch-custom_shell.html#s-custom_shell-etc" rel="section" title="9.2 System-wide vs. user-specific configuration">
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<link href="ch-X.html#s-X-starting" rel="section" title="10.1 Starting the X environment">
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<link href="ch-X.html#s-X-intro" rel="section" title="10.2 Intro: What is X">
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<link href="ch-X.html#s-X-basics" rel="section" title="10.3 Basic X operations">
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<link href="ch-X.html#s-X-startup" rel="section" title="10.4 Customizing your X startup">
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<link href="ch-text_tools.html#s-text_tools-regexps" rel="section" title="11.1 Regular expressions">
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<link href="ch-file_tools.html#s-file_tools-backup" rel="section" title="12.1 Backup tools">
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<link href="ch-file_tools.html#s-file_tools-compression" rel="section" title="12.2 File compression with <samp>gzip</samp>">
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<link href="ch-file_tools.html#s-file_tools-split" rel="section" title="12.3 Splitting files into smaller pieces">
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<link href="ch-file_tools.html#s-file_tools-find" rel="section" title="12.4 Finding files">
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<link href="ch-file_tools.html#s-file_tools-file" rel="section" title="12.5 Determining a file's contents">
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<link href="ch-disks.html#s-disks-concepts" rel="section" title="13.1 Concepts">
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<link href="ch-disks.html#s-disks-mount" rel="section" title="13.2 <samp>mount</samp> and <samp>/etc/fstab</samp>">
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<link href="ch-disks.html#s-network-ppp" rel="section" title="13.3 PPP">
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<link href="ch-dpkg.html#s-dpkg-dpkg" rel="section" title="14.1 The <code>dpkg</code> package utility">
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<link href="ch-dpkg.html#s-dpkg-what" rel="section" title="14.2 What a package maintenance utility does">
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<link href="ch-dpkg.html#s-dpkg-apt" rel="section" title="14.3 Apt">
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<link href="ch-dpkg.html#s-dpkg-dselect" rel="section" title="14.4 Using dselect.">
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<link href="ch-dpkg.html#s-dpkg-commandline" rel="section" title="14.5 Using dpkg manually">
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<link href="ch-dpkg.html#s-dpkg-compiling" rel="section" title="14.6 Compiling software yourself">
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<link href="ch-dpkg.html#s-dpkg-proprietary" rel="section" title="14.7 Proprietary software not in .deb format">
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<link href="ch-troubleshooting.html#s-troubleshooting-frozen" rel="section" title="15.1 Debian is frozen or crashed!">
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<link href="ch-troubleshooting.html#s-troubleshooting-termgarbage" rel="section" title="15.2 My terminal isn't behaving properly">
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<link href="ch-troubleshooting.html#s-troubleshooting-vi" rel="section" title="15.3 The computer beeps when I press a key, and my screen shows a text file and/or a lot of <samp>~</samp> symbols.">
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<link href="ch-advanced.html#s-advanced-scripting" rel="section" title="16.1 Introduction to shell scripting">
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<link href="ch-advanced.html#s-advanced-files" rel="section" title="16.2 Advanced files">
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<link href="ch-advanced.html#s-advanced-kernel" rel="section" title="16.3 Compiling the kernel">
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<link href="ch-advanced.html#s-advanced-security" rel="section" title="16.4 A few words on security">
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<link href="ch-advanced.html#s-advanced-programming" rel="section" title="16.5 Programming on Linux">
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<link href="ch-next.html#s-next-manuals" rel="section" title="17.1 Other Debian manuals to read">
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<link href="ch-next.html#s-next-resources" rel="section" title="17.2 Other resources">
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<link href="ch-helping.html#s-helping-bugs" rel="section" title="18.1 Submit bug reports">
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<link href="ch-helping.html#s-helping-other" rel="section" title="18.2 Other things">
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<link href="ap-apps_appendix.html#s-A_apps-whatever" rel="section" title="A.1 (Subheadings could copy the structure of the menu system)">
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<link href="ap-misc_appendix.html#s-unix-history" rel="section" title="D.1 Unix History">
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<link href="ap-misc_appendix.html#sD.2" rel="section" title="D.2 GNU/Linux History">
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<link href="ap-misc_appendix.html#sD.3" rel="section" title="D.3 The Linux kernel's version numbering">
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<link href="ch-introduction.html#s-introduction-debian-os" rel="subsection" title="2.1.1 What's an operating system, and what sort of operating system is Debian?">
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<link href="ch-introduction.html#s-introduction-debian-how" rel="subsection" title="2.1.2 Who creates Debian?">
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<link href="ch-basics.html#s-basics-commandline-description" rel="subsection" title="4.1.1 Describing the command line">
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<link href="ch-basics.html#s-basics-files-intro" rel="subsection" title="4.2.1 Introduction to files">
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<link href="ch-basics.html#s-basics-files-using" rel="subsection" title="4.2.2 Using files: a tutorial">
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<link href="ch-basics.html#s-basics-bash-completion" rel="subsection" title="4.6.1 Tab Completion">
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<link href="ch-docs.html#s-docs-support-posting" rel="subsection" title="5.5.1 Dos and Don'ts of asking a question">
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<link href="ch-shell.html#s-shell-variables-parents" rel="subsection" title="6.1.1 Parent and child processes">
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<link href="ch-shell.html#s-interactive-shells" rel="subsection" title="6.7.1 Interactive shells">
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<link href="ch-files.html#s-files-permissions-groups" rel="subsection" title="7.1.1 File Ownership">
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<link href="ch-files.html#s-files-permissions-mode" rel="subsection" title="7.1.2 Mode">
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<link href="ch-files.html#s-files-permissions-tutorial" rel="subsection" title="7.1.3 Permissions in practice">
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<link href="ch-editor.html#s-editor-vi-creating" rel="subsection" title="8.3.1 Creating a file">
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<link href="ch-editor.html#s-editor-vi-editing" rel="subsection" title="8.3.2 Editing an existing file">
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<link href="ch-editor.html#s-editor-vi-editing-movement" rel="subsection" title="8.3.2.1 Moving around in a file">
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<link href="ch-editor.html#s-editor-vi-editing-deletion" rel="subsection" title="8.3.2.2 Deleting text">
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<link href="ch-editor.html#s-editor-vi-editing-moremoving" rel="subsection" title="8.3.2.3 Sophisticated movement">
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<link href="ch-editor.html#s-editor-vi-editing-numbers" rel="subsection" title="8.3.2.4 Repeating commands">
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<link href="ch-editor.html#s-editor-vi-editing-advanced" rel="subsection" title="8.3.2.5 Advanced reference">
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<link href="ch-X.html#s-X-basics-mouse" rel="subsection" title="10.3.1 The mouse">
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<link href="ch-X.html#s-X-basics-clients" rel="subsection" title="10.3.2 X clients">
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<link href="ch-X.html#s-X-basics-trouble" rel="subsection" title="10.3.3 Troubleshooting">
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<link href="ch-X.html#s-X-basics-leaving" rel="subsection" title="10.3.4 Leaving the X environment">
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<link href="ch-disks.html#s-disks-mount-mounting" rel="subsection" title="13.2.1 Mounting a filesystem">
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<link href="ch-disks.html#s-disks-mount-cdromexample" rel="subsection" title="13.2.2 Example: Mounting a CD-ROM">
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<link href="ch-disks.html#s-disks-mount-fstab" rel="subsection" title="13.2.3 <samp>/etc/fstab</samp>: Automating the mount process">
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<link href="ch-disks.html#s-disks-mount-removable" rel="subsection" title="13.2.4 Removable disks (floppies, Zip disks, etc.)">
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<link href="ch-disks.html#s-network-ppp-introduction" rel="subsection" title="13.3.1 Introduction">
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<link href="ch-disks.html#s-network-ppp-preparation" rel="subsection" title="13.3.2 Preparation">
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<link href="ch-disks.html#s-network-ppp-wvdial" rel="subsection" title="13.3.3 The Easy Way: <samp>wvdial</samp>">
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<link href="ch-disks.html#s-network-ppp-pppd" rel="subsection" title="13.3.4 Doing It Manually">
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<link href="ch-dpkg.html#s-apt-config" rel="subsection" title="14.3.1 Configuring Apt">
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<link href="ch-dpkg.html#s-apt-usage" rel="subsection" title="14.3.2 Using apt-get.">
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<link href="ch-advanced.html#s-advanced-scripting-why" rel="subsection" title="16.1.1 What and why">
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<link href="ch-advanced.html#s-advanced-scripting-example" rel="subsection" title="16.1.2 A simple example">
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<link href="ch-advanced.html#s-advanced-files-hardlinks" rel="subsection" title="16.2.1 The real nature of files: hard links and inodes">
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<link href="ch-advanced.html#s-advanced-files-types" rel="subsection" title="16.2.2 Types of files">
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<link href="ch-advanced.html#s-advanced-files-types-symlinks" rel="subsection" title="16.2.2.1 Symbolic links">
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<link href="ch-advanced.html#s-files-misc-types-devices" rel="subsection" title="16.2.2.2 Device files">
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<link href="ch-advanced.html#s-advanced-files-types-devices-null" rel="subsection" title="16.2.2.2.1 <samp>/dev/null</samp>">
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<link href="ch-advanced.html#s-advanced-files-types-pipes" rel="subsection" title="16.2.2.3 Named pipes (FIFOs)">
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<link href="ch-advanced.html#s-advanced-files-types-sockets" rel="subsection" title="16.2.2.4 Sockets">
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<link href="ch-advanced.html#s-advanced-files-proc" rel="subsection" title="16.2.3 The <samp>proc</samp> filesystem">
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<link href="ch-advanced.html#s-advanced-files-permissions" rel="subsection" title="16.2.4 Advanced aspects of file permissions">
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<link href="ch-advanced.html#s-advanced-files-permissions-absolute" rel="subsection" title="16.2.4.1 Using numeric arguments with <samp>chmod</samp>">
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<link href="ch-advanced.html#s-advanced-files-chattr" rel="subsection" title="16.2.5 chattr">
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<link href="ch-advanced.html#s-advanced-files-copying" rel="subsection" title="16.2.6 Large-scale copying">
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<link href="ch-advanced.html#s-advanced-files-undocumented" rel="subsection" title="16.2.7 Other concepts not yet covered, but should be">
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</head>
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<body>
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<p><a name="ch-text_tools"></a></p>
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<hr>
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<p>
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[ <a href="ch-X.html">previous</a> ]
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[ <a href="index.html#contents">Contents</a> ]
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[ <a href="ch-about.html">1</a> ]
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[ <a href="ch-introduction.html">2</a> ]
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[ <a href="ch-start.html">3</a> ]
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[ <a href="ch-basics.html">4</a> ]
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[ <a href="ch-docs.html">5</a> ]
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[ <a href="ch-shell.html">6</a> ]
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[ <a href="ch-files.html">7</a> ]
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[ <a href="ch-editor.html">8</a> ]
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[ <a href="ch-custom_shell.html">9</a> ]
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[ <a href="ch-X.html">10</a> ]
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[ 11 ]
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[ <a href="ch-file_tools.html">12</a> ]
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[ <a href="ch-disks.html">13</a> ]
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[ <a href="ch-dpkg.html">14</a> ]
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[ <a href="ch-troubleshooting.html">15</a> ]
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[ <a href="ch-advanced.html">16</a> ]
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[ <a href="ch-next.html">17</a> ]
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[ <a href="ch-helping.html">18</a> ]
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[ <a href="ap-apps_appendix.html">A</a> ]
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[ <a href="ap-components_appendix.html">B</a> ]
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[ <a href="ap-booting_appendix.html">C</a> ]
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[ <a href="ap-misc_appendix.html">D</a> ]
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[ <a href="ch-file_tools.html">next</a> ]
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</p>
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<hr>
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<h1>
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Debian Tutorial (Obsolete Documentation)
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<br>Chapter 11 - Text tools
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</h1>
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<hr>
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<p>
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head, tail, grep, wc, tr, sed, perl and so on
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</p>
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<hr>
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<h2><a name="s-text_tools-regexps"></a>11.1 Regular expressions</h2>
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<p>
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A regular expression is a description of a set of characters. This description
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can be used to search through a file by looking for text that <em>matches</em>
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the regular expression. Regular expressions are analagous to shell wildcards
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(see <a href="ch-shell.html#s-shell-wildcards">Filename expansion
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("Wildcards"), Section 6.6</a>), but they are both more complicated
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and more powerful.
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</p>
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<p>
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A regular expression is made up of text and <em>metacharacters</em>. A
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metacharacter is just a character with a special meaning. Metacharacters
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include: <samp>. * [] - \ ^ $</samp>.
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</p>
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<p>
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If a regular expression contains only text (no metacharacters), then it matches
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that text. For example, the regular expression '<samp>my regular
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expression</samp>' matches the text '<samp>my regular expression</samp>', and
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nothing else. Regular expressions are usually case-sensitive.
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</p>
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<p>
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You can use the <samp>egrep</samp> command to display all lines in a file which
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contain a regular expression. Its syntax is:
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</p>
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<p>
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<samp>egrep '<var>regexp</var>' <var>filename1</var> ...</samp> [<a
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href="footnotes.html#f16" name="fr16">16</a>]
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</p>
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<p>
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For example, to find all lines in the GPL which contain the word GNU, you type:
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</p>
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<pre>
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egrep 'GNU' /usr/doc/copyright/GPL
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</pre>
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<p>
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<samp>egrep</samp> will print the lines to standard output.
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</p>
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<p>
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If you want all lines which contain <samp>freedom</samp>, followed by some
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indeterminate text, followed by <samp>GNU</samp>, you can do:
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</p>
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<pre>
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egrep 'freedom.*GNU' /usr/doc/copyright/GPL
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</pre>
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<p>
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The <samp>.</samp> means "any character"; the <samp>*</samp> means
|
|
"zero or more of the preceding thing," in this case "zero or
|
|
more of any character." So <samp>.*</samp> matches pretty much any text at
|
|
all. <samp>egrep</samp> only matches on a line-by-line basis, so
|
|
<samp>freedom</samp> and <samp>GNU</samp> have to be on the same line.
|
|
</p>
|
|
|
|
<p>
|
|
Here's a summary of regular expression metacharacters:
|
|
</p>
|
|
<dl>
|
|
<dt><samp>.</samp></dt>
|
|
<dd>
|
|
<p>
|
|
Matches any single character except newline.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>*</samp></dt>
|
|
<dd>
|
|
<p>
|
|
Matches zero or more occurences of the preceding thing. So the expression
|
|
<samp>a*</samp> matches 0 or more lowercase <samp>a</samp>, and <samp>.*</samp>
|
|
matches zero or more characters.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>[<var>characters</var>]</samp></dt>
|
|
<dd>
|
|
<p>
|
|
The brackets must contain one or more characters; the whole bracketed
|
|
expression matches exactly one character out of the set. So <samp>[abc]</samp>
|
|
matches one <samp>a</samp>, one <samp>b</samp>, or one <samp>c</samp>; it does
|
|
not match 0 characters, and it does not match a character other than these
|
|
three.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>^</samp></dt>
|
|
<dd>
|
|
<p>
|
|
Anchors your search at the beginning of the line. The expression
|
|
<samp>^The</samp> matches <samp>The</samp> only at the beginning of a line;
|
|
there can't be spaces or other text before <samp>The</samp>. If you want to
|
|
allow spaces, you can permit 0 or more space characters like this: <samp>^
|
|
*The</samp>.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>$</samp></dt>
|
|
<dd>
|
|
<p>
|
|
Anchors at the end of the line. <samp>end$</samp> requires the text
|
|
<samp>end</samp> to be at the end of the line, with no intervening spaces or
|
|
text.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>[^<var>characters</var>]</samp></dt>
|
|
<dd>
|
|
<p>
|
|
<samp>^</samp> reverses the sense of a bracketed character list. So
|
|
<samp>[^abc]</samp> matches any single character, <em>except</em> a, b, or c.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>[<var>character</var>-<var>character</var>]</samp></dt>
|
|
<dd>
|
|
<p>
|
|
You can include ranges in a bracketed character list. To match any lowercase
|
|
letter, use <samp>[a-z]</samp>. You can have more than one range; so to match
|
|
the first three or last three letters of the alphabet, try
|
|
<samp>[a-cx-z]</samp>. To get any letter, any case, try <samp>[a-zA-Z]</samp>.
|
|
You can mix ranges with single characters and with the <samp>^</samp>
|
|
metacharacter; for example, <samp>[^a-zBZ]</samp> means "anything except a
|
|
lowercase letter, capital B, or capital Z."
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>()</samp></dt>
|
|
<dd>
|
|
<p>
|
|
You can use parentheses to group parts of the regular expression, just as you
|
|
do in a mathematical expression
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>|</samp></dt>
|
|
<dd>
|
|
<p>
|
|
<samp>|</samp> means "or" --- you can use it to provide a series of
|
|
alternative expressions. Usually you want to put the alternatives in
|
|
parentheses, like this: <samp>c(ad|ab|at)</samp> matches <samp>cad</samp> or
|
|
<samp>cab</samp> or <samp>cat</samp>. Without the parentheses, it would match
|
|
<samp>cad</samp> or <samp>ab</samp> or <samp>at</samp> instead
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>\</samp></dt>
|
|
<dd>
|
|
<p>
|
|
Escapes any special characters; if you want to find a literal <samp>*</samp>,
|
|
you type <samp>\*</samp>. The slash means to ignore <samp>*</samp>'s usual
|
|
special meaning.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<p>
|
|
Here are some more examples, to help you get a feel for things:
|
|
</p>
|
|
<dl>
|
|
<dt><samp>c.pe</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>cope</samp>, <samp>cape</samp>, <samp>caper</samp>
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>c\.pe</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>c.pe</samp>, <samp>c.per</samp>
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>sto*p</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>stp</samp>, <samp>stop</samp>, <samp>stoop</samp>
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>car.*n</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>carton</samp>, <samp>cartoon</samp>, <samp>carmen</samp>
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>xyz.*</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>xyz</samp> and anything after it; some tools, like
|
|
<samp>egrep</samp>, only match until the end of the line.
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>^The</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>The</samp> at the beginning of a line
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>atime$</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>atime</samp> at the end of a line
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>^Only$</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches a line which consists solely of the word <samp>Only</samp> --- no
|
|
spaces, no other characters, nothing. Only <samp>Only</samp> is allowed
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>b[aou]rn</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>barn</samp>, <samp>born</samp>, <samp>burn</samp>
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>Ver[D-F]</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>VerD</samp>, <samp>VerE</samp>, <samp>VerF</samp>
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>Ver[^0-9]</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>Ver</samp> followed by any non-digit
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>the[ir][re]</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches <samp>their</samp>, <samp>therr</samp>, <samp>there</samp>,
|
|
<samp>theie</samp>
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
<dl>
|
|
<dt><samp>[A-Za-z][A-Za-z]*</samp></dt>
|
|
<dd>
|
|
<p>
|
|
matches any word which consists of only letters, and at least one letter. Will
|
|
not match numbers or spaces
|
|
</p>
|
|
</dd>
|
|
</dl>
|
|
|
|
<hr>
|
|
|
|
<p>
|
|
[ <a href="ch-X.html">previous</a> ]
|
|
[ <a href="index.html#contents">Contents</a> ]
|
|
[ <a href="ch-about.html">1</a> ]
|
|
[ <a href="ch-introduction.html">2</a> ]
|
|
[ <a href="ch-start.html">3</a> ]
|
|
[ <a href="ch-basics.html">4</a> ]
|
|
[ <a href="ch-docs.html">5</a> ]
|
|
[ <a href="ch-shell.html">6</a> ]
|
|
[ <a href="ch-files.html">7</a> ]
|
|
[ <a href="ch-editor.html">8</a> ]
|
|
[ <a href="ch-custom_shell.html">9</a> ]
|
|
[ <a href="ch-X.html">10</a> ]
|
|
[ 11 ]
|
|
[ <a href="ch-file_tools.html">12</a> ]
|
|
[ <a href="ch-disks.html">13</a> ]
|
|
[ <a href="ch-dpkg.html">14</a> ]
|
|
[ <a href="ch-troubleshooting.html">15</a> ]
|
|
[ <a href="ch-advanced.html">16</a> ]
|
|
[ <a href="ch-next.html">17</a> ]
|
|
[ <a href="ch-helping.html">18</a> ]
|
|
[ <a href="ap-apps_appendix.html">A</a> ]
|
|
[ <a href="ap-components_appendix.html">B</a> ]
|
|
[ <a href="ap-booting_appendix.html">C</a> ]
|
|
[ <a href="ap-misc_appendix.html">D</a> ]
|
|
[ <a href="ch-file_tools.html">next</a> ]
|
|
</p>
|
|
|
|
<hr>
|
|
|
|
<p>
|
|
Debian Tutorial (Obsolete Documentation)
|
|
</p>
|
|
|
|
<address>
|
|
29 Dezember 2009<br>
|
|
<br>
|
|
Havoc Pennington <code><a href="mailto:hp@debian.org">hp@debian.org</a></code><br>
|
|
<br>
|
|
</address>
|
|
<hr>
|
|
|
|
</body>
|
|
|
|
</html>
|
|
|