Question

What is the smallest code I can use to count the number of occurrences of the newline character in a file with objective-c / cocoa touch?

Thanks!

Answer 1

Both of the other answers are correct, but with the caveat that they require loading the entire file into memory to work.

The way around that is to load the file incrementally using an NSFileHandle. Something like this:

NSFileHandle * file = [NSFileHandle fileHandleForReadingAtPath:pathToFile];
NSUInteger chunkSize = 1024;
NSData * chunk = [file readDataOfLength:chunkSize];
NSUInteger numberOfNewlines = 0;
while ([chunk length] > 0) {
  const unichar * bytes = (const unichar *)[chunk bytes];
  for (int index = 0; index < [chunk length]; ++index) {
    unichar character = (unichar)bytes[index];
    if ([[NSCharacterSet newlineCharacterSet] characterIsMember:character]) {
      numberOfNewlines++;
    }
  }
  chunk = [file readDataOfLength:chunkSize];
}