C++ Program to extract numbers from a file that is always updating with new data

[tmlee2]

Hey guys,

I need help or any ideas on how to write a C or C++ program that extracts certain numbers out of a section after the 4, 5 and 6 space.

For Example:

The output file will produce:

[ [1900 00 0 -2.000000 0.650000 0.006000 0.020000 2.274000 0.010000 54 0 0.7 10.8 1 0 0 0.000000 17.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 18];...

So I want to extract the numbers 0.650000, 0.006000, 0.020000 because those are the 4,5,6 space after [ [

Another problem I have is that the output file I showed will always being updated constantly for instance as follow:

[ [1900 00 0 -2.000000 0.650000 0.006000 0.020000 2.2054000 0.010000 10 0 0.7 10.8 1 0 0 0.000000 17.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 13];...

[ [1900 00 0 -1.000000 0.650000 0.006000 0.020000 2.694000 0.010000 9 0 0.7 10.8 1 0 0 0.000000 17.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 10];...

[ [1900 00 0 -2.000000 0.6023000 0.04000 0.050000 2.2454000 0.010000 5 0 0.7 10.8 1 0 0 0.000000 17.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 0.000000 12];...

And it will keep updating like this and I want to update the previous numbers I extracted with now the new numbers after the 4,5, and 6 space.

So my idea is to write a code to let it know when it encounters [ [ start looking for the 4,5,6 space and get those numbers and once it reaches ;... that's the end of that section so re-look for the next section of numbers after the 4,5,6 space.

The file will be a text file or matlab file that is always being updated with these sections of numbers. Can I make this a #include<nameoffile.h> or does .h not work with a file that is always being updated. Thank you for your input and help, it is really appreciated!

[tath]

split input file into tokens with strtok(input," ") to extract what you need.
simple solution would be creating program like:

while(1)
{
if (file_updated) // ex. if modify time changed
{
open_file
split into tokens
save choosen tokens
close file
}
}

to see if the file has been modified you could use
http://msdn.microsoft.com/en-us/library/fa0hc0ht(v=vs.80).aspx to compare modify times

[tmlee2]

Thank you for your reply, the strtok function looks perfect for what I need, I will give it a try.