Counts the number of lines in a text file

Counts the number of lines in a text file by counting the number of occurrences of platform-independent newlines (CR, LF, and CR+LF [1]), including a last line with neither. An empty file has zero lines.

# S3 method for default
countLines(file, chunkSize=5e+07, ...)

Arguments

file

A connection or a pathname.

chunkSize

The number of bytes read in each chunk.

...

Not used.

Value

Returns an non-negative integer.

Details

Both compressed and non-compressed files are supported.

Author

Henrik Bengtsson

References

[1] Page Newline, Wikipedia, July 2008. https://en.wikipedia.org/wiki/Newline

Examples

pathname <- system.file("NEWS.md", package="R.utils");
n <- countLines(pathname);
n2 <- length(readLines(pathname));
stopifnot(n == n2);