Category : C++ Source Code
Archive   : IDIOMS.ZIP
Filename : 3-3.C

 
Output of file : 3-3.C contained in archive : IDIOMS.ZIP
/* Copyright (c) 1992 by AT&T Bell Laboratories. */
/* Advanced C++ Programming Styles and Idioms */
/* James O. Coplien */
/* All rights reserved. */

#include
#include
#include

class FileRef {
private:
class File &f;
char buf[1];
unsigned long ix;
public:
FileRef (File &ff, unsigned long i) : f (ff), ix (i) { }
FileRef &operator=(char c);
operator char ();
};

class File {
friend class FileRef;
public:
File(const char *name) {
fd = open(name, O_RDWR|O_CREAT, 0664);
}
~File() { close(fd); }
FileRef operator[] (unsigned long ix) {
return FileRef(*this, ix);
}
private:
int fd;
};

FileRef& FileRef::operator=(char c) {
lseek(f.fd, ix, 0); write(f.fd, &c, 1); return *this;
}

FileRef::operator char () {
lseek(f.fd, ix, 0); read(f.fd, buf, 1); return buf[0];
}

int main() {
File foo("foo");
foo[5] = '5';
foo[10] = 'l';
char c = foo[5];
cout << "c = " << c << endl;
}


  3 Responses to “Category : C++ Source Code
Archive   : IDIOMS.ZIP
Filename : 3-3.C
”

  1. Daniel says:
    January 27, 2013 at 3:59 pm

    Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!

  2. Joshie says:
    March 18, 2014 at 4:57 pm

    This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.

  3. DiskingRound says:
    January 14, 2015 at 10:57 pm

    But one thing that puzzles me is the “mtswslnkmcjklsdlsbdmMICROSOFT” string. There is an article about it here. It is definitely worth a read: http://www.os2museum.com/wp/mtswslnk/