Issue reading space from file

Question

I am trying to read a line from a file that has spaces in it. Despite everything I've tried and all my research, nothing seems to work, here is my current attemp

void read_name(fstream& in_file, comp& cmp)
{
   char buff[80];
   in_file.getline(buff, 79, '\n');
   in_file >> buff;

   cout << "NAME: " << buff << endl;

   cmp.set_name(buff);
   in_file.getline(buff, 79);
}

For whatever reason, this will still read until it sees a space and then stops. Any help would be much appreciated. I'm not that great with straight C++ so I could very well just be missing something.

score 1 · Answer 1 · answered Mar 22 '13 at 18:57

1

in_file.getline(buff, 79, '\n');

There. You read a line (assuming the line wasn't longer than 78 characters). So why'd you go and do this?

in_file >> buff;

That's going to overwrite the line you just read with the next word. If you want the next line, then call getline again.

But it's better to use std::string and the free function std::getline, that way you don't have to specify line lengths.

std::string buff;
std::getline(in_file, buff);

answered Mar 22 '13 at 18:57

Benjamin Lindley

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I tried this, but it doesn't print out anything after "NAME:" void read_name(fstream& in_file, comp& cmp) { std::string line; if (std::getline(in_file, line)) { cout << "NAME: " << line << endl; } cmp.set_name(buff); in_file.getline(buff, 79); } – roundtheworld Mar 22 '13 at 19:00
@user1595510: Then something else is going wrong, perhaps the contents of the file aren't what you expect, I don't know. I can't diagnose it without more information. http://sscce.org/ – Benjamin Lindley Mar 22 '13 at 19:07

Rich · Answer 2 · 2013-03-22T19:25:58.613

1

The line

in_file >> buff;

is wiping out the contents of buff which you've just read from the file. If you step through your code with a debugger watching the contents of buff then you would see this happening.

edited Mar 22 '13 at 19:25

answered Mar 22 '13 at 18:58

Rich

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1) This should be a comment, not an answer. 2) A file opened in text mode (the default) takes care of differences in line endings. – Benjamin Lindley Mar 22 '13 at 18:59

score 0 · Answer 3 · answered Mar 22 '13 at 18:53

0

Since you are using c++ I recommend you use stl string instead of char arrays.

std::string linestr;
while( std::getline(input, linestr) )
{
   // process line
}

where input is your ifstream.

answered Mar 22 '13 at 18:53

DiegoNolan

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And since we're using standard C++, I recommend you call the C++ standard library "the C++ standard library", and not "STL" which it isn't. – Mar 22 '13 at 18:57

Issue reading space from file

3 Answers3