read string and convert to bits?

[blinktude]

Hi
I have a txt file full of words and numbers
for example:
-------------------------------------------------
`smash the stack` [C programming] n. On many C implementations
it is possible to corrupt the execution stack by writing past
the end of an array declared auto in a routine. Code that does
this is said to smash the stack, and can cause return from the
outine to jump to a random address. This can produce some of
-------------------------------------------------
i need to read the txt file char by char and convert it into bits(i.e 10100101010).
how can I do that?

[gpraghuram]

HI,
1)Open the input file
2)use fgetc to a single character
3)sprintf it to a string using %d to get the ascii value
4)convert the bit to binary value
5)print that to another file

Hope this is what u want....

Thanks
Raghuram

[blinktude]

HI,
1)Open the input file
2)use fgetc to a single character
3)sprintf it to a string using %d to get the ascii value
4)convert the bit to binary value
5)print that to another file

Hope this is what u want....

Thanks
Raghuram

hi
thanks for the quick reply
fgetc seem to use the FILE class
for the simplicity of my code I have used ofstream. is there a way to convert from ofstream to FILE?

thanks in advnaced

[gpraghuram]

Hi,
FILE is a C Library and ofstream u have used is C++
Check for a function from the class u have used to read a single character.
Check this page for refernce
Thanks
Raghuram

[AdrianH]

HI,
1)Open the input file
2)use fgetc to a single character
3)sprintf it to a string using %d to get the ascii value
4)convert the bit to binary value
5)print that to another file

Hope this is what u want....

Thanks
Raghuram

You can do this with streams as well. Use istream::operator >>(char) and ostream::operator <<(char). Using a file in this way is not necessarily efficient though and is not portable.

A better way would be to read in the binary string, and know the length from it. Then use the left shift operator to convert.

I.e convert an 8 bit string in pseudo code (approximate, not been tested):

bitstring = "00000000"
value=0
for i=0 to 7
  value |= (bitstring[i] == '1')
end for

Hope this helps.


Adrian

[AdrianH]

bitstring = "00000000"
value=0
for i=0 to 7
  value |= (bitstring[i] == '1')
end for

Err, it should read:

bitstring = "00000000"
value=0
for i=0 to 7
  value |= ((bitstring[i] == '1') << i)
end for

Note that this is fairly simplistic and can be done in a variety of different ways.

Adrian

[sc327Ari]

blinktude do you still need "help"? Message me if you do...this is very interesting...

-Ari