Advance in the default input stream as long as comment lines are found.

In the following, the first statement skips all lines beginning with either ` #' or ` !'. The second statement skips any following blank lines:

fskipline("!#")
fskipline("\n")

This procedure advances in the input stream using the given list of comment signs as a filter. Each character of the given string is considered to be a symbol that marks the beginning of a comment line. Note that the character `\n' designates lines starting with nothing, that is, empty lines. During the parsing, spaces and tabulations are ignored.

read, readln.