Single character used to separate fields within a record.
quote
Single character used to quote strings.
na
Character vector of strings to use for missing values. Set this
option to character() to indicate no missing values.
comment
A string used to identify comments. Any text after the
comment characters will be silently ignored.
trim_ws
Should leading and trailing whitespace be trimmed from
each field before parsing it?
escape_double
Does the file escape quotes by doubling them?
i.e. If this option is TRUE, the value """" represents
a single quote, ".
escape_backslash
Does the file use backslashes to escape special
characters? This is more general than escape_double as backslashes
can be used to escape the delimeter character, the quote characer, or
to add special characters like \n.
begin, end
Begin and end offsets for each file. These are C++
offsets so the first column is column zero, and the ranges are
[begin, end) (i.e inclusive-exclusive).