/** \page tutorial Tutorial \htmlonly <style type="text/css"> body.tutorial_body { font-family: "Helvetica Neue", Verdana, Helvetica, Arial, sans-serif; font-size: 13pt; background-color: #1E335E; margin: 0; } pre { border: solid #AAA 1px; background-color: black; color: white; padding: 10px 12px; font-size: 10pt; font-family: Menlo, Monaco, "DejaVu Sans Mono", "Courier New", Courier, monospace; line-height: 140%; white-space: pre-wrap; margin-top: 10px; tab-size: 4; -moz-tab-size: 4; -o-tab-size: 4; } p { margin-bottom: 10px; margin-top: 0; color: #333333; line-height: 1.25em; } tt { font-family: monospace; } .suggest { color: #555; } pre u { border-bottom: 2px solid #0F0; text-decoration: none; } .meta { color: white; } pre b { /* Used for commands */ color: #005fd7; font-weight: normal; } pre i { /* Used for arguments */ color: #00afff; font-style: normal; } pre em { /* Used for path/help word */ color: #0a0; font-style: normal; } .quote { color: #A50; } .error { /* Used for errors */ color: #F55; font-weight: bold; } .tutorial_nav { position: relative; z-index: 2; margin-left: 10px; margin-top: 15px; } .tutorial_nav ul { padding: 0 15px; margin: 0; } .tutorial_nav li { margin: 0; line-height: normal; height: auto; color: #EEE; font-size: 12pt; font-family: "Trebuchet MS", Verdana, Arial, sans-serif; list-style-image: none; list-style-position: outside; list-style-type: none; padding: 3px 15px; margin: 0 -15px; } .tutorial_nav a { color: inherit; text-decoration: none; font-family: font-size: 12pt; } .tutorial_nav .chevron { font-family: Times, "Times New Roman"; color: #DDF; font-size: 16pt; line-height: 10pt; font-weight: bold; } .no_shadow > li > a, .no_shadow { text-shadow: none; } .nav > li > a:hover { text-decoration: none; background-color: inherit; color: #99BBFF; } /* Override some default left bar stuff */ ul.nav li { margin-bottom: 0; } .title_top { width: 100%; text-align: left; color: white; font-size: 18pt; height: 72px; z-index: 1; text-indent: 260px; } .tutorial_content { -moz-box-shadow: -5px 0px 5px -2px black; -webkit-box-shadow: -5px 0px 5px -2px black; box-shadow: -5px 0px 5px -2px black; margin-left: 280px; padding: 1px 25px 10px 10px; position: relative; z-index: 5; background-color: white; } h3 { font-size: 25px; margin-top: 12px; } h1, h2, h3 { color: #1E335E; } h1.interior_title { color: #333; padding-bottom: 10px; border-bottom: 1px solid #AAA; } h1 { font-size: 150%; } h2 { font-size: 135%; } h3 { font-size: 110%; } </style> <div class="fish_left_bar fish_left_medium"> <div class="tutorial_nav"> <ul class="nav no_shadow"> <li><a href="#tut_why_fish"><span class="chevron">›</span> Why fish?</a></li> <li><a href="#tut_learning_Fish"><span class="chevron">›</span> Learning fish</a></li> <li><a href="#tut_running_commands"><span class="chevron">›</span> Running Commands</a></li> <li><a href="#tut_getting_help"><span class="chevron">›</span> Getting Help</a></li> <li><a href="#tut_syntax_highlighting"><span class="chevron">›</span> Syntax Highlighting</a></li> <li><a href="#tut_wildcards"><span class="chevron">›</span> Wildcards</a></li> <li><a href="#tut_pipes_and_redirections"><span class="chevron">›</span> Pipes and Redirections</a></li> <li><a href="#tut_autosuggestions"><span class="chevron">›</span> Autosuggestions</a></li> <li><a href="#tut_tab_completions"><span class="chevron">›</span> Tab Completions</a></li> <li><a href="#tut_variables"><span class="chevron">›</span> Variables</a></li> <li><a href="#tut_exit_status"><span class="chevron">›</span> Exit Status</a></li> <li><a href="#tut_exports"><span class="chevron">›</span> Environment Variables</a></li> <li><a href="#tut_lists"><span class="chevron">›</span> Lists</a></li> <li><a href="#tut_command_substitutions"><span class="chevron">›</span> Command Substitutions</a></li> <li><a href="#tut_combiners"><span class="chevron">›</span> Combiners (And, Or, Not)</a></li> <li><a href="#tut_conditionals"><span class="chevron">›</span> Conditionals (If, Else, Switch)</a></li> <li><a href="#tut_functions"><span class="chevron">›</span> Functions</a></li> <li><a href="#tut_loops"><span class="chevron">›</span> Loops</a></li> <li><a href="#tut_prompt"><span class="chevron">›</span> Prompt</a></li> <li><a href="#tut_startup"><span class="chevron">›</span> Startup</a></li> </ul> </div> </div> <div class="fish_right_bar fish_right_medium"> <h1 class="interior_title">fish tutorial</h1> <h2 id="tut_why_fish">Why fish?</h2> <p>fish is a fully-equipped command line shell (like bash or zsh) that is smart and user-friendly. fish supports powerful features like syntax highlighting, autosuggestions, and tab completions that just work, with nothing to learn or configure. <p>If you want to make your command line more productive, more useful, and more fun, without learning a bunch of arcane syntax and configuration options, then fish might be just what you're looking for! <h2 id="tut_learning_Fish">Learning fish</h2> <p>This tutorial assumes a basic understanding of command line shells and Unix commands, and that you have a working copy of fish. <p>If you have a strong understanding of other shells, and want to know what fish does differently, search for the magic phrase <i>unlike other shells</i>, which is used to call out important differences. <p>When you start fish, you should see this: <pre> Welcome to fish, the friendly interactive shell Type <em>help</em> for instructions on how to use fish you@hostname <em>~</em>> </pre> <p>fish comes with a default prompt that shows your username, hostname, and working directory. You'll see <a href="#tut_prompt">how to change your prompt</a> further down. From now on, we'll pretend your prompt is just a '>' to save space. <h2 id="tut_running_commands">Running Commands</h2> <p>fish runs commands like other shells: you type a command, followed by its arguments. Spaces are separators: <pre> > <b>echo</b> <i>hello world</i> hello world </pre> You can include a literal space in an argument with a backslash, or by using single or double quotes: <pre> > <b>mkdir</b> <i>My\ Files</i> > <b>cp</b> <i>~/Some\ File</i> <i class=quote>'My Files'</i> > <b>ls</b> <i class=quote>"My Files"</i> Some File </pre> Commands can be chained with semicolons. <h2 id="tut_getting_help">Getting Help</h2> fish has excellent help and man pages. Run <tt>help</tt> to open help in a web browser, and <tt>man</tt> to open it in a man page. You can also ask for help with a specific command, for example, <tt>help set</tt> to open in a web browser, or <tt>man set</tt> to see it in the terminal. <pre> > <b>man</b> <i>set</i> set - handle environment variables Synopsis... </pre> <h2 id="tut_syntax_highlighting">Syntax Highlighting</h2> You'll quickly notice that fish performs syntax highlighting as you type. Invalid commands are colored red by default: <pre> > <b class="error">/bin/mkd</b> </pre> A command may be invalid because it does not exist, or refers to a file that you cannot execute. When the command becomes valid, it is shown in a different color: <pre> > <b>/bin/mkdir</b> </pre> fish will underline valid file paths as you type them: <pre> > <b>cat</b> <i><span style="text-decoration: underline">~/somef<u>i</u></span></i> </pre> <p>This tells you that there exists a file that starts with '<tt>somefi</tt>', which is useful feedback as you type. <p>These colors, and many more, can be changed by running <tt>fish_config</tt>, or by modifying variables directly. <h2 id="tut_wildcards">Wildcards</h2> fish supports the familiar wildcard *. To list all JPEG files: <pre> > <b>ls</b> <i>*.jpg</i> lena.jpg meena.jpg santa maria.jpg </pre> <p>You can include multiple wildcards: <pre> > <b>ls</b> <i>l*.p*</i> lena.png lesson.pdf </pre> <p>Especially powerful is the <i>recursive wildcard</i> ** which searches directories recursively: <pre> > <b>ls</b> <i>/var/**.log</i> /var/log/system.log /var/run/sntp.log </pre> <p>If that directory traversal is taking a long time, you can Control-C out of it. <h2 id="tut_pipes_and_redirections">Pipes and Redirections</h2> <p>You can pipe between commands with the usual vertical bar: <pre> > <b>echo</b> <i>hello world</i> | <b>wc</b> 1 2 12 </pre> <p>stdin and stdout can be redirected via the familiar < and >. Unlike other shells, stderr is redirected with a caret ^ <pre> > <b>grep</b> <i>fish</i> < /etc/shells > ~/output.txt ^ ~/errors.txt </pre> <h2 id="tut_autosuggestions">Autosuggestions</h2> fish suggests commands as you type, and shows the suggestion to the right of the cursor, in gray. For example: <pre> > <b class="error">/bin/h</b><span class="suggest"><u>o</u>stname</span> </pre> It knows about paths and options: <pre> > <b>grep</b> <i>--i<span class="suggest"><u>g</u>nore-case</span></i> </pre> And history too. Type a command once, and you can re-summon it by just typing a few letters: <pre> > <b>r</b><span class="suggest"><u>s</u>ync -avze ssh . myname@somelonghost.com:/some/long/path/doo/dee/doo/dee/doo</span> </pre> To accept the autosuggestion, hit right arrow or Control-F. If the autosuggestion is not what you want, just ignore it. <h2 id="tut_tab_completions">Tab Completions</h2> <p>fish comes with a rich set of tab completions, that work "out of the box." <p>Press tab, and fish will attempt to complete the command, argument, or path: <pre> > <b class="error">/pri</b><span class="meta"><tab> →</span> <b>/private/</b> </pre> <p>If there's more than one possibility, it will list them: <pre> > <b class="error">~/stuff/s</b><span class="meta"><tab></span> <i>~/stuff/s</i>cript.sh <i class="quote">(Executable, 4.8kB)</i> <i>~/stuff/s</i>ources/ <i class="quote">(Directory)</i> </pre> <p>Hit tab again to cycle through the possibilities. <p>fish can also complete many commands, like git branches: <pre> > <b>git</b> <i>merge pr</i><span class="meta"><tab> →</span> git merge prompt_designer > <b>git</b> <i>checkout b</i><span class="meta"><tab></span> <i>b</i>uiltin_list_io_merge <i class="quote">(Branch)</i> <i>b</i>uiltin_set_color <i class="quote">(Branch)</i> <i>b</i>usted_events <i class="quote">(Tag)</i> </pre> Try hitting tab and see what fish can do! <h2 id="tut_variables">Variables</h2> <p>Like other shells, a dollar sign performs <i>variable substitution</i>: <pre> > <b>echo</b> <i>My home directory is $HOME</i> My home directory is /home/tutorial </pre> Variable substitution also occurs in double quotes, but not single quotes: <pre> > <b>echo</b> <i class="quote">"My current directory is </i><i>$</i><i class="quote">PWD"</i> My current directory is /home/tutorial > <b>echo</b> <i class="quote">'My current directory is $PWD'</i> My current directory is $PWD </pre> Unlike other shells, fish has no dedicated syntax for setting variables. Instead it has an ordinary command: <tt>set</tt>, which takes a variable name, and then its value. <pre> > <b>set</b> <i>name</i> <i class="quote">'Mister Noodle'</i> > <b>echo</b> <i>$name</i> Mister Noodle </pre> <p>(Notice the quotes: without them, <tt>Mister</tt> and <tt>Noodle</tt> would have been separate arguments, and <tt>$name</tt> would have been made into a <i>list</i> of two elements.) <p>Unlike other shells, variables are <i>not</i> further split after substitution: <pre> > <b>mkdir</b> <i>$name</i> > <b>ls</b> Mister Noodle </pre> In bash, this would have created two directories "Mister" and "Noodle". In fish, it created only one: the variable had the value "Mister Noodle", so that is the argument that was passed to <span style="mono">mkdir</span>, spaces and all. <h2 id="tut_exit_status">Exit Status</h2> Unlike other shells, fish stores the exit status of the last command in <tt>$status</tt> instead of <tt>$?</tt>. <pre> > <b>false</b> > <b>echo</b> <i>$status</i> 1 </pre> Zero is considered success, and non-zero is failure. <h2 id="tut_exports">Exports (Environment Variables)</h2> Unlike other shells, fish does not have an export command. Instead, a variable is exported via an option to <tt>set</tt>, either <tt>--export</tt> or just <tt>-x</tt>. <pre> > <b>set</b> <i>-x MyVariable SomeValue</i> > <b>env</b> | <b>grep</b> <i>MyVariable</i> <span style="background: #A0A">MyVariable</span>=SomeValue </pre> You can erase a variable with <tt>-e</tt> or <tt>--erase</tt> <pre> > <b>set</b> <i>-e MyVariable</i> > <b>env</b> | <b>grep</b> <i>MyVariable</i> <span class="meta">(no output)</span> </pre> <h2 id="tut_lists">Lists</h2> <p>The <tt>set</tt> command above used quotes to ensure that <tt>Mister Noodle</tt> was one argument. If it had been two arguments, then <tt>name</tt> would have been a <i>list</i> of length 2. In fact, all variables in fish are really lists, that can contain any number of values, or none at all. <p>Some variables, like <tt>$PWD</tt>, only have one value. By convention, we talk about that variable's value, but we really mean its <i>first</i> (and only) value. <p>Other variables, like <tt>$PATH</tt>, really do have multiple values. During <i>variable expansion</i>, the variable expands to become multiple arguments: <pre> > <b>echo</b> <i>$PATH</i> /usr/bin /bin /usr/sbin /sbin /usr/local/bin </pre> <p>Lists cannot contain other lists: there is no recursion. A variable is a list of strings, full stop. <p>Get the length of a list with <tt>count</tt>: <pre> > <b>count</b> <i>$PATH</i> 5 </pre> You can append (or prepend) to a list by setting the list to itself, with some additional arguments. Here we append /usr/local/bin to $PATH: <pre> > <b>set</b> <i>PATH $PATH /usr/local/bin</i> </pre> You can access individual elements with square brackets. Indexing starts at 1 from the beginning, and -1 from the end: <pre> > <b>echo</b> <i>$PATH</i> /usr/bin /bin /usr/sbin /sbin /usr/local/bin > <b>echo</b> <i>$PATH[1]</i> /usr/bin > <b>echo</b> <i>$PATH[-1]</i> /usr/local/bin </pre> You can also access ranges of elements, known as "slices:" <pre> > <b>echo</b> <i>$PATH[1..2]</i> /usr/bin /bin > <b>echo</b> <i>$PATH[-1..2]</i> /usr/local/bin /sbin /usr/sbin /bin </pre> You can iterate over a list (or a slice) with a <i>for loop</i>: <pre> > <b>for</b> <i>val</i> <b>in</b> <i>$PATH</i> <b>echo</b> <i>"entry: $val"</i> <b>end</b> entry: /usr/bin/ entry: /bin entry: /usr/sbin entry: /sbin entry: /usr/local/bin </pre> <h2 id="tut_command_substitutions">Command Substitutions</h2> Command substitutions use the output of one command as an argument to another. Unlike other shells, fish does not use backticks ` for command substitutions. Instead, it uses parentheses: <pre> > <b>echo</b> <i>In (</i><b>pwd</b><i>), running (</i><b>uname</b><i>)</i> In /home/tutorial, running FreeBSD </pre> A common idiom is to capture the output of a command in a variable: <pre> > <b>set</b> <i>os (</i><b>uname</b><i>)</i> > <b>echo</b> <i>$os</i> Linux </pre> Command substitutions are not expanded within quotes. Instead, you can temporarily close the quotes, add the command substitution, and reopen them, all in the same argument: <pre> > <b>touch</b> <i class="quote">"testing_"</i><i>(</i><b>date</b> <i>+%s</i><i>)</i><i class="quote">".txt"</i> > <b>ls</b> <i>*.txt</i> testing_1360099791.txt </pre> <h2 id="tut_combiners">Combiners (And, Or, Not)</h2> Unlike other shells, fish does not have special syntax like && or || to combine commands. Instead it has commands <tt>and</tt>, <tt>or</tt>, and <tt>not</tt>. <pre> > <b>cp</b> <i>file1.txt file1_bak.txt</i>; <b>and echo</b> <i class="quote">"Backup successful"</i>; <b>or echo</b> <i class="quote">"Backup failed"</i> Backup failed </pre> <h2 id="tut_conditionals">Conditionals (If, Else, Switch)</h2> Use <tt>if</tt>, <tt>else if</tt>, and <tt>else</tt> to conditionally execute code, based on the exit status of a command. <pre> <b>if grep</b> <i>fish /etc/shells</i> <b>echo</b> <i>Found fish</i> <b>else if grep</b> <i>bash /etc/shells</i> <b>echo</b> <i>Found bash</i> <b>else</b> <b>echo</b> <i>Got nothing</i> <b>end</b> </pre> There is also a <tt>switch</tt> command: <pre> <b>switch</b> <i>(</i><b>uname</b><i>)</i> <b>case</b> <i>Linux</i> <b>echo</b> <i>Hi Tux!</i> <b>case</b> <i>Darwin</i> <b>echo</b> <i>Hi Hexley!</i> <b>case</b> <i>FreeBSD NetBSD DragonFly</i> <b>echo</b> <i>Hi Beastie!</i> <b>case</b> <i class="quote">'*'</i> <b>echo</b> <i>Hi, stranger!</i> <b>end</b> </pre> Note that <tt>case</tt> does not fall through, and can accept multiple arguments or (quoted) wildcards. <h2 id="tut_functions">Functions</h2> A fish function is a list of commands, which may optionally take arguments. Unlike other shells, arguments are not passed in "numbered variables" like <tt>$1</tt>, but instead in a single list <tt>$argv</tt>. To create a function, use the <tt>function</tt> builtin: <pre> > <i><b>function</b> say_hello <b>echo</b> Hello $argv <b>end</b></i> > <b>say_hello</b> Hello > <b>say_hello <i>everybody!</i></b> Hello everybody! </pre> <p>Unlike other shells, fish does not have aliases or special prompt syntax. Functions take their place. <p>You can list the names of all functions with the <tt>functions</tt> keyword (note the plural!). fish starts out with a number of functions: <pre> > <b>functions</b> alias, cd, delete-or-exit, dirh, dirs, down-or-search, eval, export, fish_command_not_found_setup, fish_config, fish_default_key_bindings, fish_prompt, fish_right_prompt, fish_sigtrap_handler, fish_update_completions, funced, funcsave, grep, help, history, isatty, ls, man, math, nextd, nextd-or-forward-word, open, popd, prevd, prevd-or-backward-word, prompt_pwd, psub, pushd, seq, setenv, sgrep, trap, type, umask, up-or-search, vared </pre> <p>You can see the source for any function by passing its name to <tt>functions</tt>: <pre> > <b>functions</b> <i>ls</i> function ls --description 'List contents of directory' command ls -G $argv end </pre> <h2 id="tut_loops">Loops</h2> While loops: <pre> > <b>while</b> <i>true</i> <b>echo</b> <i class="quote">"Loop forever"</i> <b>end</b> Loop forever Loop forever Loop forever ... </pre> For loops can be used to iterate over a list. For example, a list of files: <pre> > <b>for</b> <i>file in *.txt</i> <b>cp</b> <i>$file $file.bak</i> <b>end</b> </pre> Iterating over a list of numbers can be done with `seq`: <pre> > <b>for</b> <i>x in (</i><b>seq</b> <i>5)</i> <b>touch</b> <i>file_$x.txt</i> <b>end</b> </pre> <h2 id="tut_prompt">Prompt</h2> Unlike other shells, there is no prompt variable like PS1. To display your prompt, fish executes a function with the name <tt>fish_prompt</tt>, and its output is used as the prompt. You can define your own prompt: <pre> > <b>function <i>fish_prompt</i> echo <i>"New Prompt % "</i> end</b> New Prompt % <u> </u> </b> </pre> Multiple lines are OK. Colors can be set via <tt>set_color</tt>, passing it named ANSI colors, or hex RGB values: <pre> > <b>function</b> <i>fish_prompt</i> <b>set_color</b> <i>purple</i> <b>date</b> <i class="quote">"+%m/%d/%y"</i> <b>set_color</b> <i>FF0</i> <b>echo</b> <i>(</i><b>pwd</b><i>)</i> <i class="quote">'>'</i> <b>set_color</b> <i>normal</i> <b>end</b> <span style="color: purple">02/06/13</span> <span style="color: #FF0">/home/tutorial ></span><u> </u> </b> </pre> <p>You can choose among some sample prompts by running <tt>fish_config prompt</tt>. fish also supports RPROMPT through <tt>fish_right_prompt</tt>. <h3>$PATH</h2> <tt>$PATH</tt> is an environment variable containing the directories in which fish searches for commands. Instead of separating entries with a colon, $PATH is a list. You can modify $PATH in a few ways: <p><ol> <li>By modifying the <tt>$fish_user_paths</tt> variable, which is automatically appended to <tt>$PATH</tt>. For example, to permanently add /usr/local/bin to your <tt>$PATH</tt>, you could write: <pre> > <b>set</b> <i>-U fish_user_paths $fish_user_paths /usr/local/bin</i> </pre> <li>Directly in config.fish (see below).</li> </ol> <h2 id="tut_startup">Startup (Where's .bashrc?)</h2> <p>fish starts by executing commands in <tt>~/.config/fish/config.fish</tt>. You can create it if it does not exist. <p>It is possible to directly create functions and variables in <tt>config.fish</tt> file, using the commands shown above. For example: <p><pre> > <b>cat</b> <i>~/.config/fish/config.fish</i> set -x PATH $PATH /sbin/ function ll ls -lh $argv end </pre> <p>However, it is more common and efficient to use <i>autoloading functions</i> and <i>universal variables</i>. <h3>Autoloading Functions</h2> <p>When fish encounters a command, it attempts to <i>autoload</i> a function for that command, by looking for a file with the name of that command in <tt>~/.config/fish/functions/</tt>. <p>For example, if you wanted to have a function <tt>ll</tt>, you would add a text file <tt>ll.fish</tt> to <tt>~/.config/fish/functions</tt>: <pre> > <b>cat</b> <i>~/.config/fish/functions/ll.fish</i> function ll ls -lh $argv end </pre> This is the preferred way to define your prompt as well: <pre> > <b>cat</b> <i>~/.config/fish/functions/fish_prompt.fish</i> function fish_prompt echo (pwd) '> ' end </pre> <p>See the documentation for <a href="commands.html#funced">funced</a> and <a href="commands.html#funcsave">funcsave</a> for ways to create these files automatically. <h3>Universal Variables</h2> <p>A universal variable is a variable whose value is shared across all instances of fish, now and in the future - even after a reboot. You can make a variable universal with <tt>set -U</tt>: <pre> > <b>set</b> <i>-U EDITOR vim</i> </pre> Now in another shell: <pre> > <b>echo</b> <i>$EDITOR</i> vim </pre> <h3>Ready for more?</h2> <p>If you want to learn more about fish, there is <a href="index.html">lots of detailed documentation</a>, an <a href="https://lists.sourceforge.net/lists/listinfo/fish-users">official mailing list</a>, the IRC channel <tt>#fish</tt> on <tt>irc.oftc.net</tt>, and the <a href="http://github.com/fish-shell/fish-shell/">github page</a>. </div> \endhtmlonly