test.c

        int pid = proc->pid;
        int n, m;
        int started = 0;
        union {
                long val;
                char x[sizeof(long)];
        } u;

        if (addr & (sizeof(long) - 1)) {
                /* addr not a multiple of sizeof(long) */
                n = addr - (addr & -sizeof(long)); /* residue */
                addr &= -sizeof(long); /* residue */
                errno = 0;
                u.val = ptrace(PTRACE_PEEKDATA, pid, (char *) addr, 0);
                if (errno) {
                        if (started && (errno==EPERM || errno==EIO)) {
                                /* Ran into 'end of memory' - stupid "printpath" */
                                return 0;
                        }
                        /* But if not started, we had a bogus address. */
                        if (addr != 0 && errno != EIO && errno != ESRCH)
                                perror("ptrace: umoven");
                        return -1;
                }
                started = 1;
                memcpy(laddr, &u.x[n], m = MIN(sizeof(long) - n, len));
                addr += sizeof(long), laddr += m, len -= m;
        }
        while (len) {
                errno = 0;
                u.val = ptrace(PTRACE_PEEKDATA, pid, (char *) addr, 0);
                if (errno) {
                        if (started && (errno==EPERM || errno==EIO)) {
                                /* Ran into 'end of memory' - stupid "printpath" */
                                return 0;
                        }
                        if (addr != 0 && errno != EIO && errno != ESRCH)
                                perror("ptrace: umoven");
                        return -1;
                }
                started = 1;
                memcpy(laddr, u.x, m = MIN(sizeof(long), len));
                addr += sizeof(long), laddr += m, len -= m;
        }