awk的urlencode

echo "测试 123" |LANG=C awk 'function char2hex(char){    for(j=0;j<256;j++)    {        tmp=sprintf("%c",j);        if(tmp==char){            return sprintf("%%%X",j);        }    }    return char;}BEGIN{    FS="";    OFS="";}{    for(i=1;i<=NF;i++) $i=char2hex($i);    print;}'