a simple C++ question (about binary file input)

[news.hku.hk]

i have a binary file "myfile.bin", its output of "od -t x1 myfile.bin" is:

0000000 7f 45 4c 46 01 02 01

and longer. i want the output to screen be:

7f 45 4c 46 01 02 01

i try to write the program like that:

char ch2;
ifstream ifs ("myfile.bin", ios:binary|ios::in);
while (ifs.get(ch2)) { *****
cout.put(ch2); *****
}
ifs.close(); return 0;

i think the two lines with ***** are problematic, could anyone gives me a
helping hand? thanks for reading this post.

 

[Victor Bazarov]

i have a binary file "myfile.bin", its output of "od -t x1 myfile.bin" is:

0000000 7f 45 4c 46 01 02 01

and longer. i want the output to screen be:

7f 45 4c 46 01 02 01

i try to write the program like that:

char ch2;
ifstream ifs ("myfile.bin", ios:binary|ios::in);
while (ifs.get(ch2)) { *****
cout.put(ch2); *****

You probably want to do

cout << int(ch2) << ' ';

}
ifs.close(); return 0;

i think the two lines with ***** are problematic, could anyone gives me a
helping hand? thanks for reading this post.

Victor

 

[Nick Hounsome]

i have a binary file "myfile.bin", its output of "od -t x1 myfile.bin" is:

0000000 7f 45 4c 46 01 02 01

and longer. i want the output to screen be:

7f 45 4c 46 01 02 01

These are hex integers not chars.
cat shows chars
od shows the hexadecimal integer values of those chars (using 2 chars per
char

i try to write the program like that:

char ch2;
ifstream ifs ("myfile.bin", ios:binary|ios::in);

cout << std::hex << std::setfill('0'); // use hex for
ints and padd with leading 0

while (ifs.get(ch2)) { *****

// each char is 2 hex digits and width isn't sticky so it
must be done for each
cout << ' ' << std::setw(2) << int(ch2);

}

cout << dec << setfill(' '); // set back to default - this isn't
ideal but proper saving and restoring of state is messy