fstream operator>> stops at white space

[khalid302]

I need to read a specific number of characters into an std::string
from a file regardless of the characters read.

* fstream operator>> stops when it runs into a white space character.
* The global variant of fstream::getline works with std:string but
does not take a 'width' parameter.
* ifstream::get takes a 'width' parameter but does not work with
std::string.

I simply want to read a specific number of characters and only stop on
EOF. Is there any straight forward way to do it ?

 

[khalid302]

Resize the string first, and rely on the fact that in all (known) current

implementations it has contiguous buffer, and that will be guaranteed in C++0x.

I think std:string automatically accommodates input from operator>>.
am I missing something ?

 

[Ian Collins]

I think std:string automatically accommodates input from operator>>.
am I missing something ?

I think Alf was telling you to do an unformatted read directly into the
string's buffer.

 

[khalid302]

I think Alf was telling you to do an unformatted read directly into the
string's buffer.

What's the API for that, std::string has data() and c_str(), and both
return a const char* which can't/shouldn't be modified.

 

[khalid302]

The only solution I could think of, is to create a custom stream class
over cstdio ... C streams seem to be more mature.

 

[Ian Collins]

What's the API for that, std::string has data() and c_str(), and both
return a const char* which can't/shouldn't be modified.

&string[0]

 

[Juha Nieminen]

The only solution I could think of, is to create a custom stream class
over cstdio ... C streams seem to be more mature.

std::string buffer(width, ' ');
inputFile.read(&buffer[0], width);

What's so hard about that?

 

[khalid302]

  What's so hard about that?

Nothing, just never crossed my mind, thanks

 

[khalid302]

&string[0]

Yeah, thanks.