--- system(command)
--- system(program[, arg1[, arg2[, ...]]])

    command ¹Ԥơ(ҥץλơ 0
    ǽλ)ˤϿ򡢼Ԥ(ޥɤ¹ԤǤʤä
    ޤ)ˤϵ֤ޤλơѿ $? 
    ȤǤޤ

    ޥɤ¹Ԥ뤳ȤǤʤä硢¿Υϥơ
    127 ֤ޤ(ä $? οͤϡ0x7f00)
    ʤ Ruby λҥץơ 127 ǽλޤ
    ɤ¹ԤǤʤäΤޥɤԤΤϡ
    $? 򻲾Ȥ뤳ȤȽ̲ǽǤ

    ¾εư˴ؤƤ exec 򻲾Ȥ
    

    `command` [Ȥ߹ߴؿ/"`"], open ⻲ȤƤ
    

