sprunge script supporting both curl and wget

sprunge.sh

#!/bin/sh

has_command() {
    which "$1" >/dev/null 2>&1
}

urlencode() {
    python -c '
import sys
import urllib

data = sys.stdin.read()
urlencoded = urllib.quote(data)
print(urlencoded)
'
}

if has_command curl; then
    sprungecommand="curl -sS -F sprunge=<- http://sprunge.us"
elif has_command wget && has_command python; then
    wget_wrapper() { wget -q -O - --post-data="sprunge=$(urlencode)" http://sprunge.us; }
    sprungecommand="wget_wrapper"
else
    printf 'No suitable HTTP utility found for sprunging! :(\n' >&2
    exit 1
fi

sprunge() {
    $sprungecommand
    err=$?
    if [ $err -ne 0 ]; then
        printf 'Failed to sprunge %s :(\n' "$file" >&2
    fi
    return $err
}

if [ "X$1" = 'X' -o "X$1" = 'X-' ]; then
    sprunge
else
    for file in "$@"; do
        # Become responsive if terminal.
        if [ -t 1 ]; then
            printf '%s: ' "$file"
        else
            [ "X$multiple" != 'X' ] && printf ' '
        fi

        sprunged="$(sprunge < "$file")"
        err=$?

        # Figure out file extension for url argument.
        if printf "$file"|grep -qF '.'; then
            url="$sprunged?$(printf "$file"|awk -F . '{print $NF}')"
        else
            url="$sprunged"
        fi

        if [ $err -eq 0 ]; then
            printf '%s' "$url"
            if [ -t 1 ]; then
                echo
            fi
        fi
        multiple=yes
    done
fi