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                <ol class="chapter"><li class="chapter-item expanded affix "><a href="../intro.html">Introduction</a></li><li class="chapter-item expanded "><a href="../tools/index.html"><strong aria-hidden="true">1.</strong> Tools</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../tools/zsh.html"><strong aria-hidden="true">1.1.</strong> zsh</a></li><li class="chapter-item expanded "><a href="../tools/bash.html"><strong aria-hidden="true">1.2.</strong> bash</a></li><li class="chapter-item expanded "><a href="../tools/fish.html" class="active"><strong aria-hidden="true">1.3.</strong> fish</a></li><li class="chapter-item expanded "><a href="../tools/tmux.html"><strong aria-hidden="true">1.4.</strong> tmux</a></li><li class="chapter-item expanded "><a href="../tools/git.html"><strong aria-hidden="true">1.5.</strong> git</a></li><li class="chapter-item expanded "><a href="../tools/awk.html"><strong aria-hidden="true">1.6.</strong> awk</a></li><li class="chapter-item expanded "><a href="../tools/emacs.html"><strong aria-hidden="true">1.7.</strong> emacs</a></li><li class="chapter-item expanded "><a href="../tools/gpg.html"><strong aria-hidden="true">1.8.</strong> gpg</a></li><li class="chapter-item expanded "><a href="../tools/gdb.html"><strong aria-hidden="true">1.9.</strong> gdb</a></li><li class="chapter-item expanded "><a href="../tools/gdbserver.html"><strong aria-hidden="true">1.10.</strong> gdbserver</a></li><li class="chapter-item expanded "><a href="../tools/radare2.html"><strong aria-hidden="true">1.11.</strong> radare2</a></li><li class="chapter-item expanded "><a href="../tools/qemu.html"><strong aria-hidden="true">1.12.</strong> qemu</a></li><li class="chapter-item expanded "><a href="../tools/pacman.html"><strong aria-hidden="true">1.13.</strong> pacman</a></li><li class="chapter-item expanded "><a href="../tools/dot.html"><strong aria-hidden="true">1.14.</strong> dot</a></li></ol></li><li class="chapter-item expanded "><a href="../monitor/index.html"><strong aria-hidden="true">2.</strong> Resource analysis & monitor</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../monitor/lsof.html"><strong aria-hidden="true">2.1.</strong> lsof</a></li><li class="chapter-item expanded "><a href="../monitor/ss.html"><strong aria-hidden="true">2.2.</strong> ss</a></li><li class="chapter-item expanded "><a href="../monitor/pidstat.html"><strong aria-hidden="true">2.3.</strong> pidstat</a></li><li class="chapter-item expanded "><a href="../monitor/pgrep.html"><strong aria-hidden="true">2.4.</strong> pgrep</a></li><li class="chapter-item expanded "><a href="../monitor/pmap.html"><strong aria-hidden="true">2.5.</strong> pmap</a></li><li class="chapter-item expanded "><a href="../monitor/pstack.html"><strong aria-hidden="true">2.6.</strong> pstack</a></li></ol></li><li class="chapter-item expanded "><a href="../trace_profile/index.html"><strong aria-hidden="true">3.</strong> Trace and Profile</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../trace_profile/strace.html"><strong aria-hidden="true">3.1.</strong> strace</a></li><li class="chapter-item expanded "><a href="../trace_profile/ltrace.html"><strong aria-hidden="true">3.2.</strong> ltrace</a></li><li class="chapter-item expanded "><a href="../trace_profile/perf.html"><strong aria-hidden="true">3.3.</strong> perf</a></li><li class="chapter-item expanded "><a href="../trace_profile/oprofile.html"><strong aria-hidden="true">3.4.</strong> OProfile</a></li><li class="chapter-item expanded "><a href="../trace_profile/time.html"><strong aria-hidden="true">3.5.</strong> time</a></li></ol></li><li class="chapter-item expanded "><a href="../binary/index.html"><strong aria-hidden="true">4.</strong> Binary</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../binary/od.html"><strong aria-hidden="true">4.1.</strong> od</a></li><li class="chapter-item expanded "><a href="../binary/xxd.html"><strong aria-hidden="true">4.2.</strong> xxd</a></li><li class="chapter-item expanded "><a href="../binary/readelf.html"><strong aria-hidden="true">4.3.</strong> readelf</a></li><li class="chapter-item expanded "><a href="../binary/objdump.html"><strong aria-hidden="true">4.4.</strong> objdump</a></li><li class="chapter-item expanded "><a href="../binary/nm.html"><strong aria-hidden="true">4.5.</strong> nm</a></li></ol></li><li class="chapter-item expanded "><a href="../development/index.html"><strong aria-hidden="true">5.</strong> Development</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../development/c++filt.html"><strong aria-hidden="true">5.1.</strong> c++filt</a></li><li class="chapter-item expanded "><a href="../development/c++.html"><strong aria-hidden="true">5.2.</strong> c++</a></li><li class="chapter-item expanded "><a href="../development/glibc.html"><strong aria-hidden="true">5.3.</strong> glibc</a></li><li class="chapter-item expanded "><a href="../development/gcc.html"><strong aria-hidden="true">5.4.</strong> gcc</a></li><li class="chapter-item expanded "><a href="../development/cmake.html"><strong aria-hidden="true">5.5.</strong> cmake</a></li><li class="chapter-item expanded "><a href="../development/make.html"><strong aria-hidden="true">5.6.</strong> make</a></li><li class="chapter-item expanded "><a href="../development/ld.so.html"><strong aria-hidden="true">5.7.</strong> ld.so</a></li><li class="chapter-item expanded "><a href="../development/symbolver.html"><strong aria-hidden="true">5.8.</strong> symbol versioning</a></li><li class="chapter-item expanded "><a href="../development/python.html"><strong aria-hidden="true">5.9.</strong> python</a></li><li class="chapter-item expanded "><a href="../development/gcov.html"><strong aria-hidden="true">5.10.</strong> gcov</a></li><li class="chapter-item expanded "><a href="../development/pgo.html"><strong aria-hidden="true">5.11.</strong> pgo</a></li></ol></li><li class="chapter-item expanded "><a href="../linux/index.html"><strong aria-hidden="true">6.</strong> Linux</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../linux/systemd.html"><strong aria-hidden="true">6.1.</strong> systemd</a></li><li class="chapter-item expanded "><a href="../linux/coredump.html"><strong aria-hidden="true">6.2.</strong> coredump</a></li><li class="chapter-item expanded "><a href="../linux/ptrace_scope.html"><strong aria-hidden="true">6.3.</strong> ptrace_scope</a></li><li class="chapter-item expanded "><a href="../linux/cryptsetup.html"><strong aria-hidden="true">6.4.</strong> cryptsetup</a></li><li class="chapter-item expanded "><a href="../linux/swap.html"><strong aria-hidden="true">6.5.</strong> swap</a></li><li class="chapter-item expanded "><a href="../linux/input.html"><strong aria-hidden="true">6.6.</strong> input</a></li><li class="chapter-item expanded "><a href="../linux/acl.html"><strong aria-hidden="true">6.7.</strong> acl</a></li><li class="chapter-item expanded "><a href="../linux/zfs.html"><strong aria-hidden="true">6.8.</strong> zfs</a></li></ol></li><li class="chapter-item expanded "><a href="../network/index.html"><strong aria-hidden="true">7.</strong> Network</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../network/tcpdump.html"><strong aria-hidden="true">7.1.</strong> tcpdump</a></li><li class="chapter-item expanded "><a href="../network/firewall-cmd.html"><strong aria-hidden="true">7.2.</strong> firewall-cmd</a></li><li class="chapter-item expanded "><a href="../network/nftables.html"><strong aria-hidden="true">7.3.</strong> nftables</a></li></ol></li><li class="chapter-item expanded "><a href="../web/index.html"><strong aria-hidden="true">8.</strong> Web</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../web/html.html"><strong aria-hidden="true">8.1.</strong> html</a></li><li class="chapter-item expanded "><a href="../web/css.html"><strong aria-hidden="true">8.2.</strong> css</a></li><li class="chapter-item expanded "><a href="../web/chartjs.html"><strong aria-hidden="true">8.3.</strong> chartjs</a></li></ol></li><li class="chapter-item expanded "><a href="../arch/index.html"><strong aria-hidden="true">9.</strong> Arch</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="../arch/x86_64.html"><strong aria-hidden="true">9.1.</strong> x86_64</a></li><li class="chapter-item expanded "><a href="../arch/arm64.html"><strong aria-hidden="true">9.2.</strong> arm64</a></li><li class="chapter-item expanded "><a href="../arch/armv7.html"><strong aria-hidden="true">9.3.</strong> armv7</a></li><li class="chapter-item expanded "><a href="../arch/riscv.html"><strong aria-hidden="true">9.4.</strong> riscv</a></li></ol></li></ol>
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                        <h1 id="fish1"><a class="header" href="#fish1">fish(1)</a></h1>
<h2 id="quick-info"><a class="header" href="#quick-info">Quick Info</a></h2>
<p>Fish initialization file <code>~/.config/fish/config.fish</code></p>
<p>Switch between different key bindings:</p>
<ul>
<li><code>fish_default_key_bindings</code> to use default key bindings</li>
<li><code>fish_vi_key_bindings</code> to use vi key bindings</li>
</ul>
<h2 id="variables"><a class="header" href="#variables">Variables</a></h2>
<p>Available scopes</p>
<ul>
<li><code>local</code> variable local to a block</li>
<li><code>global</code> variable global to shell instance</li>
<li><code>universal</code> variable universal to all shell instances + preserved across
shell restart</li>
</ul>
<h3 id="setunset-variables"><a class="header" href="#setunset-variables">Set/Unset Variables</a></h3>
<pre><code class="language-text">set &lt;name&gt; [&lt;values&gt;]
    -l  local scope
    -g  global scope
    -U  universal scope
    -e  erase variable
    -S  show verbose info
    -x  export to ENV
    -u  unexport from ENV
</code></pre>
<h3 id="special-variables-ref"><a class="header" href="#special-variables-ref">Special Variables <a href="https://fishshell.com/docs/current/language.html#special-variables">ref</a></a></h3>
<pre><code class="language-sh">$status      # exit code of last command
$pipestatus  # list of exit codes of pipe chain

$CMD_DURATION   # runtime of last command in ms
</code></pre>
<h3 id="lists"><a class="header" href="#lists">Lists</a></h3>
<p>In <code>fish</code> all variables are lists (start with index <code>1</code>, but lists can't
contain lists.</p>
<pre><code class="language-sh">set foo a b c d

echo $foo[1]      # a
echo $foo[-1]     # d
echo $foo[2..3]   # b c
echo $foo[1 3]    # a c
</code></pre>
<p><code>$</code> can be seen as dereference operator.</p>
<pre><code class="language-sh">set foo a; set a 1337
echo $$foo  # outputs 1337
</code></pre>
<p>Cartesian product.</p>
<pre><code class="language-sh">echo file.{h,cc}
# file.h file.cc

echo {a,b}{1,2}
# a1 b1 a2 b2
</code></pre>
<h4 id="path-ref"><a class="header" href="#path-ref"><code>*PATH</code> <a href="https://fishshell.com/docs/current/language.html#path-variables">ref</a></a></h4>
<p>Lists ending with <code>PATH</code> are automatically split at <code>:</code> when used and joined
with <code>:</code> when quoted or exported to the environment.</p>
<pre><code class="language-sh">set -x BLA_PATH a:b:c:d
echo $BLA_PATH           # a b c d
echo &quot;$BLA_PATH&quot;         # a:b:c:d          (quoted)
env | grep BLA_PATH      # BLA_PATH=a:b:c:d (env)

set FOO_PATH x y z
echo $FOO_PATH           # x y z
echo &quot;$FOO_PATH&quot;         # x:y:z
</code></pre>
<h2 id="command-handling"><a class="header" href="#command-handling">Command Handling</a></h2>
<pre><code class="language-sh"># sub-commands are not run in quotes
echo &quot;ls output: &quot;(ls)
</code></pre>
<h3 id="io-redirection"><a class="header" href="#io-redirection">I/O redirection</a></h3>
<pre><code class="language-sh"># 'noclobber', fail if 'log' already exists
echo foo &gt;? log
</code></pre>
<h2 id="control-flow"><a class="header" href="#control-flow">Control Flow</a></h2>
<h3 id="if--else"><a class="header" href="#if--else"><code>if</code> / <code>else</code></a></h3>
<pre><code class="language-sh">if grep foo bar
    # do sth
else if grep foobar bar
    # do sth else
else
    # do sth else
end
</code></pre>
<h3 id="switch"><a class="header" href="#switch"><code>switch</code></a></h3>
<pre><code class="language-sh">switch (echo foo)
case 'foo*'
    # do start with foo
case bar dudel
    # do bar and dudel
case '*'
    # do else
end
</code></pre>
<h3 id="while-loop"><a class="header" href="#while-loop"><code>while</code> Loop</a></h3>
<pre><code class="language-sh">while true
    echo foo
end
</code></pre>
<h3 id="for-loop"><a class="header" href="#for-loop"><code>for</code> Loop</a></h3>
<pre><code class="language-sh">for f in (ls)
    echo $f
end
</code></pre>
<h2 id="functions"><a class="header" href="#functions">Functions</a></h2>
<p>Function arguments are passed via <code>$argv</code> list.</p>
<pre><code class="language-sh">function fn_foo
    echo $argv
end
</code></pre>
<h3 id="autoloading"><a class="header" href="#autoloading">Autoloading</a></h3>
<p>When running a command fish attempts to autoload a function. The shell looks
for <code>&lt;cmd&gt;.fish</code> in the locations defined by <code>$fish_function_path</code> and loads
the function lazily if found.</p>
<p>This is the preferred way over monolithically defining all functions in a
startup script.</p>
<h3 id="helper"><a class="header" href="#helper">Helper</a></h3>
<pre><code class="language-sh">functions         # list al functions
functions foo     # describe function 'foo'
functions -e foo  # erase function 'foo'

funced foo        # edit function 'foo'
                  # '-e vim' to edit in vim
</code></pre>
<h3 id="argument-parsing-and-completion"><a class="header" href="#argument-parsing-and-completion">Argument parsing and completion</a></h3>
<p><code>argparse</code> puts options into variables of name <code>_flag_NAME</code>.</p>
<p>References:</p>
<ul>
<li><a href="https://fishshell.com/docs/current/language.html#argument-handling">Argument Handling</a></li>
<li><a href="https://fishshell.com/docs/current/cmds/argparse.html"><code>argparse</code></a></li>
<li><a href="https://fishshell.com/docs/current/completions.html">Writing your own completions</a></li>
<li><a href="https://fishshell.com/docs/current/cmds/complete.html"><code>complete</code></a></li>
</ul>
<pre><code class="language-sh">function moose --d &quot;my moose fn&quot;
    # h/help   : short / long option (boolean)
    # color    : only long option (boolean)
    # u/user=  : option with required argument, only last specified is taken
    # f/file+= : option with required argument, can be specified multiple times
    #
    argparse h/help color= u/user= f/file=+ -- $argv
    or return

    if set -ql _flag_help
        echo &quot;usage ...&quot;
        return 0
    end

    set -ql _flag_file
    and echo &quot;file=$_flag_file | cnt:&quot; (count $_flag_file)

    set -ql _flag_color
    and echo &quot;color=$_flag_color&quot;

    set -ql _flag_user
    and echo &quot;user=$_flag_user&quot;
end

# Delete all previous defined completions for 'moose'.
complete -c moose -e

# Don't complete files for command.
complete -c moose --no-files

# Help completion.
#   -n specifies a conditions. The completion is only active if the command
#      returns 0.
complete -c moose -s h -l help -n &quot;not __fish_contains_opt -s h help&quot; \
    --description &quot;Print usage help and exit&quot;

# File completion.
#   -F force complete files (overwrite --no-files).
#   -r requires argument.
complete -c moose -s f -l file -F -r \
    --description &quot;Specify file (can be passed multiple times)&quot;

# Color completion.
#    -a options for completion.
#    -x short for -r and --no-files (-f)
complete -c moose -x -l color -a &quot;red blue&quot; \
    --description &quot;Specify a color.&quot;

# User completion.
#    -a options for completion. Call a function to generate arguments.
complete -c moose -x -s u -l user -a &quot;(__fish_complete_users)&quot; \
    --description &quot;Specify a user&quot;
</code></pre>
<h2 id="prompt"><a class="header" href="#prompt">Prompt</a></h2>
<p>The prompt is defined by the output of the <code>fish_prompt</code> function.</p>
<pre><code class="language-sh">function fish_prompt
    set -l cmd_ret
    echo &quot;&gt; &quot;(pwd) $cmd_ret&quot; &quot;
end
</code></pre>
<blockquote>
<p>Use <code>set_color</code> to manipulate terminal colors and <code>set_color -c</code> to print the
current colors.</p>
</blockquote>
<h2 id="useful-builtins"><a class="header" href="#useful-builtins">Useful Builtins</a></h2>
<p>List all builtins with <code>builtins -n</code>.</p>
<pre><code class="language-sh"># history
history search &lt;str&gt;   # search history for &lt;str&gt;
history merge          # merge histories from fish sessions

# list
count $var             # count elements in list

contains /bin $PATH    # return 0 (true) 1 (false)
contains -i /bin $PATH # additionally print index on stdout

# string
string split SEP STRING

# math
math -b hex 4096       # output dec as hex
math 0x1000            # output hex as dec
math &quot;log2(1024)&quot;      # call functions
math -s0 7/3           # integer division (by default float)

# status
status -f              # abs path of current file
</code></pre>
<h2 id="keymaps"><a class="header" href="#keymaps">Keymaps</a></h2>
<pre><code class="language-text">  Shift-Tab .............. tab-completion with search
  Alt-Up / Alt-Down ...... search history with token under the cursor
  Alt-l .................. list content of dir under cursor
  Alt-p .................. append '2&gt;&amp;1 | less;' to current cmdline
  Alt-Left / Alt - Right . prevd / nextd, walk dir history
</code></pre>
<h2 id="debug"><a class="header" href="#debug">Debug</a></h2>
<pre><code class="language-text">  status print-stack-trace .. prints function stacktrace (can be used in scripts)
  breakpoint ................ halt script execution and gives shell (C-d | exit
                              to continue)
</code></pre>

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