Return char array from function

[dushantha12]

Hi,

I am developing a " .a " library file. Inside of that library there are some functions. I have an encryption function for encrypt some text data. My problem is I am passing the plain data as char array into the function. After encrption process done I want to return it as a char array but it's not return.

My code :

int encrypt(char *plainData, char *encryptData){
   
   int status;
   
    // encrpypting...

   Print(encryptData); // encrypted data is printing well

   return status;

}

int main(){
   char encryptedData[300];
   char plainData[] = "1234567890";
   
   if(0 < encrypt(plainData,encryptedData)){
       
       Print(encryptedData); // Output is 0000000000000
       
   }
}

Please help.

thank you.

[dushantha12]

Any comment ???

[ajh32]

Well in the code you have given you haven't populated the char[] encryptedData with anything. If I just do:

#include <iostream>
using namespace std;

void Print(char* data)
{
	cout << data << endl;
}

int encrypt(char* plainData, char* encryptData)
{   
   int status(1);
    // encrpypting...
	strcpy(encryptData, "encrypted data");

   Print(encryptData); // encrypted data is printing well

   return status;
}

int main()
{
   char encryptedData[300];
   char plainData[] = "1234567890";
   
   if(0 < encrypt(plainData, encryptedData))
	{
       Print(encryptedData); // Output is 0000000000000
   }
}

All is fine. If I were you I would use std::string. Then you would need to pass by reference.

[dushantha12]

Hi,

Thanks for the reply. In my case I am using " C " as my programming language. Any idea??

Thank you.

[ajh32]

In my case I am using " C " as my programming language. Any idea??

Well, if you were to populate the char array as I did above, you should be fine.

[dushantha12]

Hi,

Before I make the " .a " file it is working properly. After make it, link it into my project, compile and install into POS terminal then it's not working. I don't know what to do.

Thank you.

[ajh32]

Are you sure you are populating your char array named encryptData in the encrypt(...) function? How about writing the value of this variable out to a file?