[philosophyincode]

Hello,

I am confused as to how to read in a file (of indeterminate size) of longs in c++.

Thus far, I figure something like

while(!inStream.eof())
{
//read in longs here
}

is the basis but I am not sure of what method to use to read in the longs from a file that has each one placed on a separate line. Ex. 89
98
100000000000

Any help would be appreciated. Thanks

[Salem_c]

long int myVar;
while ( inStream >> myVar ) {
  // do something
}

Normally, you should avoid using eof() in a loop test.
http://sourceforge.n....php?title=Feof

[Mohanddo]

Create a char buffer, use fscanf with %s type specifier.

Then use atol() to convert it from char to an int.

[janotte]

Mohanddo, on 11 October 2010 - 09:49 PM, said:

Create a char buffer, use fscanf with %s type specifier.

Then use atol() to convert it from char to an int.

Right idea IMO but why do it in C code when we are writing in C++?
Use a string, not a char buffer.
http://www.cplusplus...ference/string/
Use getline(), not fscanf.
http://www.cplusplus...string/getline/
Use a stringstream, not atoi()
http://www.cplusplus...m/stringstream/

[Mohanddo]

Quote

Right idea IMO but why do it in C code when we are writing in C++?
Use a string, not a char buffer.
http://www.cplusplus...ference/string/
Use getline(), not fscanf.
http://www.cplusplus...string/getline/
Use a stringstream, not atoi()
http://www.cplusplus...m/stringstream/

Thanks.
Can i ask is there any particular problems with using c style functions in c++? I am much more comfortable managing files with C than C++.

This post has been edited by Mohanddo: 11 October 2010 - 07:32 AM

[Anarion]

Mohanddo, on 11 October 2010 - 04:57 PM, said:

Can i ask is there any particular problems with using c style functions in c++? I am much more comfortable managing files with C than C++.

Then you should write your programs in C. My question is, why not use what C++ provides you with? Why make things harder for yourself when the right tools are already within your grasp?

And also, here's a tutorial by bench, on reading files in C++ and the fact about eof.

This post has been edited by Anarion: 11 October 2010 - 08:26 AM