Android NDK : got exception randomly on orientation change

Question

I am trying to implement beginner NDK application .

Program runs and giving output but sometimes on Orientation change ,

it gives error

03-03 16:48:24.992: D/dalvikvm(21338): No JNI_OnLoad found in /data/app-lib/com.example.ndkdemo_scan-1/libnative.so 0x41fe7b90, skipping init

03-03 16:48:25.018: A/libc(21338): Fatal signal 11 (SIGSEGV) at 0x5f0f605c (code=2), thread 21338 (le.ndkdemo_scan)

I am writing my code below :

#include <jni.h>
#include <stdio.h>
#include <string.h>

jstring Java_com_example_ndkdemo_scan_MainActivity_getString(JNIEnv * env,jobject object , jstring s){

    const char *string1  = (*env)->GetStringUTFChars(env,s,NULL);

    if(string1==NULL) return NULL;
    char *c = "input is :%s";
    printf(c,string1);
    char out[129];
    printf("Enter A String : ");
    scanf("%s",out);
    printf("String entered is :%s",out);

    strcat(string1,string1);

    jstring string_to_return = (*env)->NewStringUTF(env,string1);
    return string_to_return;
}