gistfile1.sh

#!/bin/env bash
# example pipe commands:
#   'while read u; firefox $u; done' -- useful to pipe urls into programs that don't handle them from stdin
# the first line of every cache file is the pipe command used for that file

# dmenu defaults
if [ -f ~/.dmenurc ]; then
    source ~/.dmenurc
else
    DMENU="dmenu"
fi

# commandline argument handling
verbose="false"
pipe="/bin/bash"
for p in "$@"; do
    if [ "$p" = "-v" ]; then
        verbose="true"
    else
        pipe="$p"
    fi
done

# cache file setup
if [ "x$XDG_CACHE_HOME" = "x" ]; then
    cachefile="${HOME}/.cache"
else
    cachefile="$XDG_CACHE_HOME"
fi
cachefile="${cachefile}/xrun/$(echo \"$pipe\" | md5sum | cut -d' ' -f1)"
if [ ! -d $(dirname $cachefile) ]; then
    mkdir -p $(dirname $cachefile)
fi
if [ ! -f "$cachefile" ]; then
    echo "$pipe" > "$cachefile"
fi

# command gathering
cmd=$(tail -n +2 "$cachefile" | $DMENU -l 7 -p "$pipe" )
if [ "x$cmd" = "x" ]; then
    exit 0
fi

# command caching
echo "$cmd" >> "$cachefile"
tail -n +2 "$cachefile" | sort | uniq > "$cachefile.$$"
echo "$pipe" > "$cachefile"
cat "$cachefile.$$" >> "$cachefile"
rm "$cachefile.$$"

# command execution
hash $(echo $cmd | cut -d ' ' -f1) 2>/dev/null
if [ $? == 1 ]; then
    notify-send -- "not found: $cmd"
fi

if [[ $verbose == "true" ]]; then
    output=$(echo "$cmd" | sh -c "$pipe" 2>&1 | sed -e 's|<|\&lt;|g' -e 's|>|\&gt;|g' )
    [ "$output" != "" ] && notify-send -- "$output"
else
    echo "$cmd" | sh -c "$pipe"
fi