Reading from two text files....

[jaredgalen]

There seems to be a few more people using this forum so here's the Question.
I have a program that reads in a 32-digit hex number from the command line:
ie. findkey a3 1f 2e 3c 4e 5a f6 a3 1f 2e 37 d5 66 1a 33 3c

I take this and split it up into two arrays.
The first 8 go into the input[] array.
The next 8 go into the cipherInput[] array as in the code below.
What I need to do is instead of taking it from the command line, I want to read it from two files.
The first 8 will come from one file, the last 8 will come from another file.
I had been passing it from java, but that was a temp hack.
Can someone help me with this.
//current code//

for (i=0;i<8;i++)
sscanf(argv,&quot;%x&quot;,&input); //reading from cmd line

for (i=8;i<16;i++)
sscanf(argv,&quot;%x&quot;,&cipherInput[i-8]);

for (i=0;i<8;i++)
data=input[7-i];
//putting into the arrays
for (i=0;i<8;i++)
cipherData=cipherInput[7-i];

In summary I need to:
Read in from the first file and put that into input[]
Read in from the second file and put that into cipherInput[]
I have to read from the same line number in each file, both files are gauranteed to have the same number of lines.

Each file format is:
a3 1f 2e 3c 4e 5a f6 a3
1f 2e 37 d5 66 1a 33 3c
.
.
.

 

[jaredgalen]

Here's what I'm trying, reading from the file, one line,
putting that into a char array.
I tried using sscanf with that array but it didn't work.
I not familiar with this at all so could really use some help.
I know the indexing in the sscnaf line is all wrong I'm just trying to get it to work.

char buffer[24];
ifstream plainFile ("output/example.txt");
if (! plainFile.is_open())
  {cout << &quot;Error opening file&quot;; exit (1);}

  while (! plainFile.eof()) {
    plainFile.getline (buffer,24);
    for (i=0;i<8;i++){
      sscanf(buffer[i],&quot;%x&quot;,&cipherInput[i]);
      printf(&quot;%x&quot;,cipherInput[i]);
    }
  }

 

[azimuth0]

The program you're writing there is in C++, not C. However....

You've at least diagnosed the problem correctly.

buffer[i]

in the sscanf line references a single char - the one within the i-indexed char array. Since you're using C++ anyway, this might be simpler:

string buf;
ifstream plainFile ("output/example.txt");

if (!plainFile.good()) {
   cout << &quot;Error opening file&quot;; exit (1);
}

for (i = 0;i < 8 && !plainFile.eof();i++) {
   plainFile >> buf;
   sscanf(buf, &quot;%x&quot;, &cipherInput[i]);
   printf(&quot;%x\n&quot;, cipherInput[i]);
}

-

http://www.sanctuary.org/~azimuth/

 

[jaredgalen]

Thanks for the reply, heres what I ended up using.
Sorry for posting in the C forum but the C++ one seemed to have no activity.
I learnt a lot taday, thanks.

plainFile.getline (plainBuffer,24); 
*plainPoint = &plainBuffer[0];      

for (i=0;i<8;i++){
sscanf(*plainPoint,&quot;%x&quot;,&input[i]);
*plainPoint = *plainPoint+3;
}

jG