.shrc

# .shrc
# Common aliases and functions for all Bourne-like shells

# This script expects "whence_w" to be defined as a shell builtin, alias,
# or function which given the argument foo outputs the string "alias" if
# an alias "foo" is defined.

# Tolerate missing a specific terminal type if we have a more generic version
# (e.g., substitute screen for screen-256color)
screen_colors=$(tput colors 2>/dev/null)
if [[ -z "${screen_colors}" && "$TERM" == tmux* ]]; then
	TERM=screen${TERM##tmux}
	screen_colors=$(tput colors 2>/dev/null)
fi
while [[ "$TERM" == *-* && -z "${screen_colors}" ]]; do
	TERM=${TERM%-*}
	screen_colors=$(tput colors 2>/dev/null)
done
: ${screen_colors:=1}

# Give a default useful prompt for a shell that I have no configuration for
# This prompt does not use any shell-specific features
if [ x = "x$PS1" ]; then
	[ $(id -u) -eq 0 ] && PS1='# ' || PS1='$ '
fi
case $PS1 in
  ?' ') PS1="$LOGNAME@$(uname -n) $(basename $0|sed -e 's/^-//')$PS1" ;;
esac

alias lt-gdb="libtool --mode=execute gdb"
alias lt-valgrind="libtool --mode=execute valgrind"
alias head='head -n $(($LINES-5))'
alias tail='tail -n $(($LINES-5))'
alias vis="cat -v"

# Colorization and other support for colorization in GNU tools.  If we don't
# have GNU tools, use POSIX options that give us something close to what we
# want.
if [ "$screen_colors" -ge 8 ]; then
	if [ "x$OSTYPE" = xlinux -o "x$OSTYPE" = xlinux-gnu ]; then
		alias ls="ls --color=auto"
		alias grep='grep --color=auto --exclude=".*.sw?" --exclude="*~" --exclude=tags'
	elif [ "x$(uname -s)" = xFreeBSD ]; then
		alias ls='ls -G'
	fi
	if [ -e "$HOME/.dircolors.$TERM" ]; then
		eval `dircolors --sh $HOME/.dircolors.$TERM`
	elif [ -e "$HOME/.dircolors" ]; then
		eval `dircolors --sh $HOME/.dircolors`
	fi

	if diff --color=auto /dev/null /dev/null 2>/dev/null; then
		alias diff="diff -up --color=auto"
	elif whence_w colordiff >/dev/null 2>&1; then
		alias diff="colordiff -up"
	fi
fi
[ "x$(whence_w ls)" = xalias ] || alias ls='ls -F'
[ "x$(whence_w diff)" = xalias ] || alias diff='diff -up'

# Run a command repeatedly until it fails
whileok ()
{
	while "$@"; do :; done
	return $?
}

# gpg-agent requires this environment variable to be set
export GPG_TTY=$(tty)