X-Git-Url: https://ruderich.org/simon/gitweb/?a=blobdiff_plain;f=zsh%2Frc;h=ee2737b833a4c5976dc378119baa06872d882c0f;hb=e88bcead0b83f3d5bf2507f971e5c9d27417c9fc;hp=0724afcc5c94de5c1ea3f7816aa80b86a2f131f3;hpb=d94a9346215294a2f5258a110fb1c2c6443530f2;p=config%2Fdotfiles.git

diff --git a/zsh/rc b/zsh/rc
index 0724afc..ee2737b 100644
--- a/zsh/rc
+++ b/zsh/rc
@@ -11,6 +11,9 @@ bindkey -v
 # Be paranoid, new files are readable/writable by me only.
 umask 077
 
+# Disable beeps.
+setopt nobeep
+
 # Prevent overwriting existing files with '> filename', use '>| filename'
 # (or >!) instead.
 setopt noclobber
@@ -32,20 +35,33 @@ setopt ignoreeof
 
 # FUNCTION SETTINGS
 
+# Make sure every entry in $fpath is unique.
+typeset -U fpath
+# ~/.zsh/functions/completion is a symbolic link to the Completion directory
+# of a Zsh CVS checkout. Use it to get the newest completions if available.
+if [[ -d ~/.zsh/functions/completion ]]; then
+    fpath=(~/.zsh/functions/completion/*/*(/) $fpath)
+fi
 # Set correct fpath to allow loading my functions (including completion
 # functions).
 fpath=(~/.zsh/functions $fpath)
 # Autoload my functions (except completion functions and hidden files). Thanks
 # to caphuso from the Zsh example files for this idea.
-autoload ${fpath[1]}/^_*(^/:t)
+if [[ -d ~/.zsh/functions ]]; then
+    autoload ${fpath[1]}/^_*(^/:t)
+fi
 
-# Simulate hooks using _functions arrays for Zsh versions older then 4.3.4. At
-# the moment only precmd() and preexec() are simulated.
-if [[ $ZSH_VERSION != (4.3.<4->|4.<4->*|<5->*) ]]; then
+# Simulate hooks using _functions arrays for Zsh versions older than 4.3.4. At
+# the moment only precmd(), preexec() and chpwd() are simulated.
+#
+# At least 4.3.4 (not sure about later versions) has an error in add-zsh-hook
+# so the compatibility version is used there too.
+if [[ $ZSH_VERSION != (4.3.<5->|4.<4->*|<5->*) ]]; then
     # Provide add-zsh-hook which was added in 4.3.4.
-    fpath=($fpath ~/.zsh/functions/compatibility)
+    fpath=(~/.zsh/functions/compatibility $fpath)
 
-    # Run all functions defined in the ${precmd,preexec}_functions arrays.
+    # Run all functions defined in the ${precmd,preexec,chpwd}_functions
+    # arrays.
     function precmd() {
         for function in $precmd_functions; do
             $function $@
@@ -56,17 +72,25 @@ if [[ $ZSH_VERSION != (4.3.<4->|4.<4->*|<5->*) ]]; then
             $function $@
         done
     }
+    function chpwd() {
+        for function in $chpwd_functions; do
+            $function $@
+        done
+    }
 fi
 
 # Autoload add-zsh-hook to add/remove zsh hook functions easily.
 autoload -Uz add-zsh-hook
 
+# Load zmv (zsh move) which is powerful to rename files.
+autoload zmv
+
 
 # HISTORY SETTINGS
 
 # Use history and store it in ~/.zsh/history.
-HISTSIZE=5000
-SAVEHIST=5000
+HISTSIZE=50000
+SAVEHIST=50000
 HISTFILE=~/.zsh/history
 # Append to the history file instead of overwriting it and do it immediately
 # when a command is executed.
@@ -74,9 +98,33 @@ setopt appendhistory
 setopt incappendhistory
 # If the same command is run multiple times store it only once in the history.
 setopt histignoredups
-# Vim like completions of previous executed commands.
-bindkey "^P" history-beginning-search-backward
-bindkey "^N" history-beginning-search-forward
+# Vim like completions of previous executed commands (also enter Vi-mode). If
+# called at the beginning it just recalls old commands (like cursor up), if
+# called after typing something, only lines starting with the typed are
+# returned. Very useful to get old commands quickly. Thanks to Mikachu in #zsh
+# on Freenode (2010-01-17 12:47) for the information how to a use function
+# with bindkey.
+zle -N my-vi-history-beginning-search-backward
+my-vi-history-beginning-search-backward() {
+    local not_at_beginning_of_line
+    if [[ $CURSOR -ne 0 ]]; then
+        not_at_beginning_of_line=yes
+    fi
+
+    zle history-beginning-search-backward
+
+    # Start Vi-mode and stay at the same position (Vi-mode moves one left,
+    # this counters it).
+    zle vi-cmd-mode
+    if [[ -n $not_at_beginning_of_line ]]; then
+        zle vi-forward-char
+    fi
+}
+bindkey "^P" my-vi-history-beginning-search-backward
+bindkey -a "^P" history-beginning-search-backward # binding for Vi-mode
+# Here only Vi-mode is necessary as ^P enters Vi-mode and ^N only makes sense
+# after calling ^P.
+bindkey -a "^N" history-beginning-search-forward
 
 
 # PROMPT SETTINGS
@@ -84,18 +132,36 @@ bindkey "^N" history-beginning-search-forward
 # Use colorized output, necessary for prompts and completions.
 autoload -U colors && colors
 
+# Some shortcuts for colors. The %{...%} tells zsh that the data in between
+# doesn't need any space, necessary for correct prompt draw.
+local red="%{${fg[red]}%}"
+local blue="%{${fg[blue]}%}"
+local green="%{${fg[green]}%}"
+local yellow="%{${fg[yellow]}%}"
+local default="%{${fg[default]}%}"
+
 # Set the default prompt. The current host and working directory is displayed,
 # the exit code of the last command if it wasn't 0, the number of running jobs
-# if not 0 and a + if this shell is running inside another shell.
+# if not 0.
+#
 # The prompt is in green and blue to make easily detectable, the error exit
 # code in red and bold and the job count in yellow.
-PROMPT="%{${fg[green]}%}%B%m%b%{${fg[default]}%}:\
-%{${fg[blue]}%}%B%~%b%{${fg[default]}%} \
-%(1j.%{${fg[yellow]}%}%j%{${fg[default]}%}.)%(2L.+.)%# \
-%(?..(%{${fg[red]}%}%B%?%b%{${fg[default]}%}%) )"
+PROMPT="$green%B%m%b$default:$blue%B%~%b$default \
+%(1j.$yellow%j$default.)%# \
+%(?..($red%B%?%b$default%) )"
+
+# vcs_info was added in 4.3.9 but it works in earlier versions too. So load it
+# if the necessary files are available in ~/.zsh/functions/vcs_info (often a
+# symbolic link to current checkout of Zsh's sources).
+if [[ $ZSH_VERSION == (4.3.<9->|4.<4->*|<5->*) ||
+      -d ~/.zsh/functions/vcs_info ]]; then
+    # Update fpath to allow loading the vcs_info functions.
+    if [[ -d ~/.zsh/functions/vcs_info ]]; then
+       fpath=(~/.zsh/functions/vcs_info/
+              ~/.zsh/functions/vcs_info/Backends
+              $fpath)
+    fi
 
-# VCS_Info was added in 4.3.9.
-if [[ $ZSH_VERSION == (4.3.<9->|4.<4->*|<5->*) ]]; then
     # Allow substitutions and expansions in the prompt, necessary for
     # vcs_info.
     setopt promptsubst
@@ -103,43 +169,88 @@ if [[ $ZSH_VERSION == (4.3.<9->|4.<4->*|<5->*) ]]; then
     autoload -Uz vcs_info
     # Only look for git and mercurial repositories; the only I use.
     zstyle ':vcs_info:*' enable git hg
-    # Set style of vcs_info display. The current branch (green) and vcs (blue)
+    # Check the repository for changes so they can be used in %u/%c (see
+    # below). This comes with a speed penalty for bigger repositories.
+    zstyle ':vcs_info:*' check-for-changes true
+
+    # Set style of vcs_info display. The current branch (green) and VCS (blue)
     # is displayed. If there is an special action going on (merge, rebase)
-    # it's also displayed (red).
-    zstyle ':vcs_info:*' formats \
-    "(%{${fg[green]}%}%b%{${fg[default]}%}:\
-%{${fg[blue]}%}%s%{${fg[default]}%})"
-    zstyle ':vcs_info:*' actionformats \
-    "(%{${fg[green]}%}%b%{${fg[default]}%}/\
-%{${fg[red]}%}%a%{${fg[default]}%}:\
-%{${fg[blue]}%}%s%{${fg[default]}%})"
+    # it's also displayed (red). Also display if there are unstaged or staged
+    # (%u/%c) changes.
+    if [[ $ZSH_VERSION == (4.3.<11->|4.<4->*|<5->*) ||
+          -d ~/.zsh/functions/vcs_info ]]; then
+        zstyle ':vcs_info:*' formats \
+            "($green%b%u%c$default:$blue%s$default)"
+        zstyle ':vcs_info:*' actionformats \
+            "($green%b%u%c$default/$red%a$default:$blue%s$default)"
+    else
+        # In older versions %u and %c are not defined yet and are not
+        # correctly expanded.
+        zstyle ':vcs_info:*' formats \
+            "($green%b$default:$blue%s$default)"
+        zstyle ':vcs_info:*' actionformats \
+            "($green%b$default/$red%a$default:$blue%s$default)"
+    fi
+    # Set style for formats/actionformats when unstaged (%u) and staged (%c)
+    # changes are detected in the repository; check-for-changes must be set to
+    # true for this to work. Thanks to Bart Trojanowski
+    # (http://jukie.net/~bart/blog/pimping-out-zsh-prompt) for the idea
+    # (2010-03-11 00:20).
+    zstyle ':vcs_info:*' unstagedstr '¹'
+    zstyle ':vcs_info:*' stagedstr   '²'
+
     # Call vcs_info as precmd before every prompt.
     prompt_precmd() {
         vcs_info
     }
     add-zsh-hook precmd prompt_precmd
 
-    # Display the vcs information in the right prompt.
-    RPROMPT='${vcs_info_msg_0_}'
+    # Display the VCS information in the right prompt.
+    if [[ $ZSH_VERSION == (4.3.<9->|4.<4->*|<5->*) ]]; then
+        RPROMPT='${vcs_info_msg_0_}'
+    # There is a bug in Zsh below 4.3.9 which displays a wrong symbol when
+    # ${vcs_info_msg_0_} is empty. Provide a workaround for those versions,
+    # thanks to Frank Terbeck <ft@bewatermyfriend.org> for it.
+    else
+        RPROMPT='${vcs_info_msg_0_:- }'
+    fi
 fi
 
-# When screen or xterm is used set the name of the window to the currently
-# running program.
+unset red blue green yellow default
+
+# When screen, xterm or rxvt is used set the name of the window to the
+# currently running program.
 #
 # When a program is started preexec() sets the window's name to it; when it
-# stops precmd() resets the windows' name to 'zsh'.
-if [[ $TERM == screen || $TERM == xterm* ]]; then
-    # Set to a non empty value to reset the window name in the next precmd()
-    # call.
+# stops precmd() resets the window's name to 'zsh'.
+#
+# It works with screen, xterm and rxvt.
+#
+# If a command is run with sudo or if the shell is running as root then a ! is
+# added at the beginning of the command to make this clear. If a command is
+# running on a different computer with ssh a @ is added at the beginning. If
+# screen is running on the remote machine instead of @screen @:hostname
+# (hostname replaced by the machine's hostname) is displayed. This only works
+# if the .zshrc on the server also uses this command.
+if [[ $TERM == screen* || $TERM == xterm* || $TERM == rxvt* ]]; then
+    # Is set to a non empty value to reset the window name in the next
+    # precmd() call.
     window_reset=yes
+    # Is set to a non empty value when the shell is running as root.
+    if [[ $(id -u) -eq 0 ]]; then
+        window_root=yes
+    fi
 
     window_preexec() {
         # Get the program name with its arguments.
         local program_name=$1
+
         # When sudo is used use real program name instead, but with an
-        # exclamation mark at the beginning.
+        # exclamation mark at the beginning (handled below).
+        local program_sudo=
         if [[ $program_name == sudo* ]]; then
-            program_name=!${program_name#sudo }
+            program_name=${program_name#sudo }
+            program_sudo=yes
         fi
         # Remove all arguments from the program name.
         program_name=${program_name%% *}
@@ -147,7 +258,7 @@ if [[ $TERM == screen || $TERM == xterm* ]]; then
         # Ignore often used commands which are only running for a very short
         # time. This prevents a "blinking" name when it's changed to "cd" for
         # example and then some milliseconds later back to "zsh".
-        [[ $program_name == (cd*|ls|la|ll|clear) ]] && return
+        [[ $program_name == (cd*|ls|la|ll|clear|c) ]] && return
 
         # Change my shortcuts so the real name of the program is displayed.
         case $program_name in
@@ -160,11 +271,29 @@ if [[ $TERM == screen || $TERM == xterm* ]]; then
             m)
                 program_name=mutt
                 ;;
-            v|vi)
+            v)
                 program_name=vim
                 ;;
         esac
 
+        # Add an exclamation mark at the beginning if running with sudo or if
+        # running zsh as root.
+        if [[ -n $program_sudo || -n $window_root ]]; then
+            program_name=!$program_name
+        fi
+
+        # Add an at mark at the beginning if running through ssh on a
+        # different computer.
+        if [[ -n $SSH_CONNECTION ]]; then
+            program_name="@$program_name"
+
+            # If screen is running in SSH then display "@:hostname" as title
+            # in the term/outer screen.
+            if [[ $program_name == @screen ]]; then
+                program_name="@:${$(hostname)//.*/}"
+            fi
+        fi
+
         # Set the window name to the currently running program.
         window_title "$program_name"
 
@@ -177,20 +306,36 @@ if [[ $TERM == screen || $TERM == xterm* ]]; then
         [[ -z $window_reset ]] && return
 
         # Reset the window name to 'zsh'.
-        window_title "zsh"
+        local name="zsh"
+        # If the function was called with an argument then reset the window
+        # name to '.zsh' (used by clear alias).
+        if [[ -n $1 ]]; then
+            name=".zsh"
+        fi
+
+        # Prepend prefixes like in window_preexec().
+        if [[ -n $SSH_CONNECTION ]]; then
+            window_title "@$name"
+        elif [[ -n $window_root ]]; then
+            window_title "!$name"
+        else
+            window_title $name
+        fi
 
         # Just reset the name, so no screen reset necessary for the moment.
         window_reset=
     }
 
-    # Sets the window title. Works with screen and xterm.
-    window_title() {
-        if [[ $TERM == screen ]]; then
+    # Sets the window title. Works with screen, xterm and rxvt.
+    if [[ $TERM == screen* ]]; then
+        window_title() {
             print -n "\ek$1\e\\"
-        elif [[ $TERM == xterm* ]]; then
+        }
+    elif [[ $TERM == xterm* || $TERM == rxvt* ]]; then
+        window_title() {
             print -n "\e]2;$1\e\\"
-        fi
-    }
+        }
+    fi
 
     # Add the preexec() and precmd() hooks.
     add-zsh-hook preexec window_preexec
@@ -204,132 +349,186 @@ fi
 # (coloring, scrollable).
 zmodload zsh/complist
 # Use new completion system, store dumpfile in ~/.zsh/cache to prevent
-# cluttering of ~/.
+# cluttering of ~/. $fpath must be set before calling this. Thanks to Adlai in
+# #zsh on Freenode (2009-08-07 21:05) for reminding me of the $fpath problem.
 autoload -U compinit && compinit -d ~/.zsh/cache/zcompdump
+
+# Use cache to speed up completions.
+zstyle ':completion:*' use-cache on
+zstyle ':completion:*' cache-path ~/.zsh/cache
+
+# Complete arguments and fix spelling mistakes when possible.
+zstyle ':completion:*' completer _complete _match _correct _approximate
+
 # Make sure the list of possible completions is displayed after pressing <TAB>
 # the first time.
 setopt nolistambiguous
 # Allow completions in the middle of a text, i.e. "/usr/bin/<TAB>whatever"
 # completes like "/usr/bin/<TAB>". Useful when adding new options to commands.
 bindkey "^I" expand-or-complete-prefix
-# Use cache to speed up completions.
-zstyle ':completion:*' use-cache on
-zstyle ':completion:*' cache-path ~/.zsh/cache
 # Try uppercase if the currently typed string doesn't match. This allows
 # typing in lowercase most of the time and completion fixes the case.
 zstyle ':completion:*' matcher-list '' 'm:{a-z}={A-Z}'
-# Ignore completion functions.
-zstyle ':completion:*:functions' ignored-patterns '_*'
-# Ignore parent directory.
-zstyle ':completion:*:(cd|mv|cp):*' ignore-parents parent pwd
+
 # Use ls like colors for completions.
 zstyle ':completion:*' list-colors ${(s.:.)LS_COLORS}
+
 # Make completion lists scrollable so "do you wish to see all n possibilities"
 # is no longer displayed.
 zstyle ':completion:*' list-prompt '%p'
-# When unsetting variables make sure every variable name is only suggested
-# once.
-zstyle ':completion:*:unset:*' ignore-line yes
-# When working with Mercurial and Git don't complete the same file multiple
-# times. Very useful when completing file names.
-zstyle ':completion:*:(hg|git)*:*' ignore-line yes
-
+# Display group name (like 'external command', 'alias', etc.) when there are
+# multiple matches in bold.
+zstyle ':completion:*' format '    %B%d%b:'
+# Display different types of matches separately.
+zstyle ':completion:*' group-name ''
 
-# CUSTOM ALIASES AND FUNCTIONS
+# Ignore completion functions.
+zstyle ':completion:*:functions' ignored-patterns '_*'
+# Ignore parent directory.
+zstyle ':completion:*:(cd|mv|cp):*' ignore-parents parent pwd
+# Always complete one value (file name) only once in the current line. This
+# makes it easy to complete multiple values because I can just press tab to
+# get all possible values. Otherwise I would have to skip the first value
+# again and again.
+zstyle ':completion:*' ignore-line yes
+# Except for mv and cp, because I often want to use to similar names, so I
+# complete to the same and change it.
+zstyle ':completion:*:(mv|cp):*' ignore-line no
 
-# Simplify calls to less, automatically redirects all output.
-alias -g L='2>&1 | less'
-# Simplify calls to colordiff, output is also piped through less.
-alias -g D='2>&1 | colordiff L'
-# Simplify calls to grep.
-alias -g G='| grep'
 
-# Automatically use unified diffs.
-alias diff='diff -u'
+# CUSTOM ALIASES AND FUNCTIONS
 
-# Display all files and use human readable sizes.
-alias du='du -sh'
+# If ^C is pressed while typing a command, add it to the history so it can be
+# easily retrieved later and then abort like ^C normally does. This is useful
+# when I want to abort an command to do something in between and then finish
+# typing the command.
+#
+# Thanks to Vadim Zeitlin <vz-zsh@zeitlins.org> for a fix (--) so lines
+# starting with - don't cause errors.
+TRAPINT() {
+    # Store the current buffer in the history.
+    zle && print -s -- $BUFFER
 
-# Use human readable sizes.
-alias df='df -h'
+    # Return the default exit code so Zsh aborts the current command.
+    return $1
+}
 
-# Multiple files given to Vim are opened in tabs, supported since Vim 7.
-if [[ ${${${(f)"$(vim --version)"}[1]#VIM - Vi IMproved }%% *} == 7* ]]; then
-    alias vim='vim -p'
+# Colorize stderr. Very useful when looking for errors. Thanks to
+# http://gentoo-wiki.com/wiki/Zsh for the basic script and Mikachu in #zsh on
+# Freenode (2010-03-07 04:03) for some improvements (-r, printf). It's not yet
+# perfect and doesn't work with some interactive stderr output, but in those
+# cases the E alias can be used as workaround.
+exec 2>>(while read -r line; do
+    printf '\e[91m%s\e[0m\n' "$line"
+    print -n $'\0';
+done &)
+
+# Load aliases and similar functions also used by other shells.
+if [[ -f ~/.shell/aliases ]]; then
+    . ~/.shell/aliases
 fi
 
-# Shortcuts for often used programs.
-alias e='elinks'
-alias g='git'
-alias m='mutt'
-alias v='vim'
-alias vi='vim'
-
-# I sometimes confuse editor and shell, print a warning to prevent I exit the
-# shell.
-alias :q='echo "This is not Vim!" >&2'
+# Make sure aliases are expanded when using sudo.
+alias sudo='sudo '
 
-# Edit the mercurial patch queue series file for the current mercurial
-# repository in Vim. Also change Vim's pwd to the patches directory so other
-# patches can easily be opened.
-alias vqs='vim -c "cd $(hg root)/.hg/patches/" "$(hg root)/.hg/patches/series"'
+# Global aliases for often used commands in the command line.
+alias -g E='2>&1'
+alias -g L='E | less'
+alias -g D='E | colordiff L'
+alias -g G='| grep'
+alias -g S='| sort'
+alias -g U='| uniq'
+alias -g H='| head'
+alias -g T='| tail'
 
 # Make going up directories simple.
 alias -g ...='../..'
 alias -g ....='../../..'
 alias -g .....='../../../..'
 
-# Improved ls which displays the files in columns (-C), visualizes
-# directories, links and other special files (-F) and pages everything through
-# less (L).
-#
-# If available use GNU ls with colorized output. If it isn't available use
-# normal ls which needs CLICOLOR_FORCE so it displays colors when used with a
-# pager.
-ls --color &> /dev/null
-if [[ $? -eq 0 ]]; then
-    alias ls='ls --color'
-else
-    alias ls='CLICOLOR_FORCE=1 ls -G'
+# If the window naming feature is used (see above) then use ".zsh" (leading
+# dot) as title name after running clear so it's clear to me that the window
+# is empty. I open so much windows that I don't know in which I have something
+# important. This helps me to remember which windows are empty (I run clear
+# after I finished my work in a window).
+if [[ -n $window_reset ]]; then
+    alias clear='clear; window_reset=yes; window_precmd reset'
 fi
-# Main ls function.
-function ls() {
-    command ls -C -F $* L
-}
-# Helper function to list all files.
-function la() {
-    ls -a $*
+
+# Display all branches (except stash) in gitk but only 200 commits as this is
+# much faster. Also put in the background and disown. Thanks to sitaram in
+# #git on Freenode (2009-04-20 15:51).
+gitk() {
+    command gitk \
+        --max-count=200 \
+        $(git rev-parse --symbolic-full-name --remotes --branches) \
+        $@ &
+    disown %command
 }
-# Helper function to list all files in list format with access rights, etc.
-function ll() {
-    la -l $*
+# Same for tig (except the disown part as it's no GUI program).
+tig() {
+    command tig \
+        --max-count=200 \
+        $(git rev-parse --symbolic-full-name --remotes --branches) \
+        $@
 }
 
-# If ^C is pressed while typing a command, add it to the history so it can be
-# easily retrieved later and then abort like ^C normally does. This is useful
-# when I want to abort an command to do something in between and then finish
-# typing the command.
-TRAPINT() {
-    # Store the current buffer in the history.
-    zle && print -s $BUFFER
 
-    # Return the default exit code so zsh aborts the current command.
-    return $1
-}
+# OS SPECIFIC SETTINGS
+
+local uname=$(uname)
+
+if [[ $uname == Linux ]]; then
+    # Settings when creating Debian packages.
+    DEBEMAIL=simon@ruderich.org
+    export DEBEMAIL
+    DEBFULLNAME="Simon Ruderich"
+    export DEBFULLNAME
+
+elif [[ $uname == Darwin ]]; then # Mac OS X
+    # Store the current clipboard in CLIPBOARD before every command so it can
+    # be used in commands.
+    os_darwin_preexec() {
+        export CLIPBOARD="$(pbpaste)"
+    }
+    # Add the function as preexec hook.
+    add-zsh-hook preexec os_darwin_preexec
+
+    # Initialize CLIPBOARD so it's available for completion directly after
+    # startup.
+    CLIPBOARD=""
+    export CLIPBOARD
+
+    # Fetch current URL in clipboard with wget.
+    alias wnc='wget --no-proxy $CLIPBOARD'
+fi
 
-# Display TODOs stored in ~/.todo if this file exists.
-todo() {
-    if [[ -f ~/.todo ]]; then
-        cat ~/.todo | $PAGER
-    fi
-}
 
+# LOAD ADDITIONAL CONFIGURATION FILES
 
-# Load rc file for current OS.
-source_config ~/.zsh os rc $(uname) nolocal
 # Load rc file for current hostname (first part before a dot) or rc.local.
 source_config ~/.zsh host rc ${$(hostname)//.*/}
 
+
+# RUN COMMANDS
+
+# If not already in screen reattach to a running session or create a new one.
+#
+# screen* is necessary as `screen` uses screen.linux for example for a linux
+# console which would otherwise cause an infinite loop.
+if [[ $TERM != screen* && $TERM != 'dumb' ]]; then
+    # Get running detached sessions.
+    session=$(screen -list | grep 'Detached' | awk '{ print $1; exit }')
+    # Create a new session if none is running.
+    if [[ -z $session ]]; then
+        screen
+    # Reattach to a running session.
+    else
+        screen -r $session
+    fi
+fi
+
+
 source_debug "finished sourcing ~/.zsh/rc"
 
 # vim: ft=zsh