// ezptrace.c
// source: http://stackoverflow.com/questions/7697344/why-doesnt-ptrace-singlestep-work-properly

#include <sys/user.h>
#include <sys/ptrace.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <unistd.h>
#include <stdio.h>

int main() {
    pid_t child;
    child = fork();
    if (child == 0) {
        char *argv[] = { "ezptraceme", NULL };
        ptrace(PTRACE_TRACEME, 0, NULL, NULL);
        execv(argv[0], argv);
    }
    else {

        int status;
        wait(&status);
//        struct user_regs_struct regs;
        int stepno = 0;
        while (1) {
//            ptrace(PTRACE_GETREGS, child, NULL, &regs);
//            printf("eip: %x\n", (unsigned int) regs.eip);
            printf("step %d\n", stepno++);
            ptrace(PTRACE_SINGLESTEP, child, NULL, NULL);
            waitpid(child, &status, 0);
            if(WIFEXITED(status)) break;
        }
        printf("end\n");
    }
    return 0;
}