Error position in the data file.

Question

Here's the odd behavior of the data.table fread () method after updating 1.8.1> 1.9.2.

a.txt: "id";"Timestamp" "1";"2013-10-19,01:42:11" 

This does not work:

 > a <- fread("a.txt") Error in fread("a.txt") : Not positioned correctly after testing format of header row. ch=';' 

Ok, so I greatly simplified this example, and I still cannot figure out where my mistake is!

Unescaping id fixes it:

 1;"2013-10-19,01:42:11" 

Removing id fixes it:

 "2013-10-19,01:42:11" 

Saving id is escaped and simplifies timestamping:

 "1", "2013-10-19" 

So why does this error occur? I'm at a dead end.