binary reading

[ruby talk]

a=File.open("c:\\1.txt")
a.binmode
print a.read(1)

it prints the char. how can i get and play with the bits and bytes of the file?

 

[Zach Dennis]

a=File.open("c:\\1.txt")
a.binmode
print a.read(1)

it prints the char. how can i get and play with the bits and bytes of the file?

a=File.open("c:\\1.txt")
a.each_byte{ |byte|
#play with each character/byte here
}


Zach

 

[ruby talk]

hmm... i really wanted the binary. is there a to_b?

 

[Bill Atkins]

Are you sure you want the binary? You can use the bitwise |, ~, and &
operators to manipulate the bits of the byte.

 

[Eric Hodel]

hmm... i really wanted the binary. is there a to_b?

I think you want to look at String#unpack.

 

[ruby talk]

I looked at the unpack example
a=File.open("c:\\1.txt")
a.each_byte { |byte|
print byte.to_s.unpack('b8'),' ',byte,' '
}

But i get this for output
01101100 65 01101100 66
i know A!=B
and b* instead of b8 gives me
0110110010101100 65 0110110001101100 66

Becker

 

[Hugh Sasse Staff Elec Eng]

What about (written as if it were a patch):

- a=File.open("c:\\1.txt")
+ a=File.open("c:\\1.txt", 'rb')
a.each_byte { |byte|
- print byte.to_s.unpack('b8'),' ',byte,' '
+ print byte.chr.unpack('b8'),' ',byte,' '
}


Hugh

 

[Robert Klemme]

I looked at the unpack example
a=File.open("c:\\1.txt")
a.each_byte { |byte|
print byte.to_s.unpack('b8'),' ',byte,' '
}

But i get this for output
01101100 65 01101100 66
i know A!=B
and b* instead of b8 gives me
0110110010101100 65 0110110001101100 66

%08b\n", b.chr,b,b) } }
V 86 01010110
e 101 01100101
r 114 01110010
s 115 01110011
i 105 01101001
o 111 01101111
n 110 01101110
32 00100000
4 52 00110100
.. 46 00101110
4 52 00110100
32 00100000
B 66 01000010
u 117 01110101
i 105 01101001
l 108 01101100
d 100 01100100
32 00100000
1 49 00110001
6 54 00110110
2 50 00110010
=> #<File:buildnumber (closed)>

Regards

robert

 

[ruby talk]

10000010 65 01000010 66

the output is still wrong
I also tried adding a.binmode no luck.
Will i also have such a problem writing a binary file?
Becker

 

[Mauricio Fernández]

10000010 65 01000010 66

the output is still wrong

It's printing the LSB first. unpack("B8") would do what you expect.
Alternatively num.to_s(2) or "%08b" % num .