Openssl code: crypto.h bio_lib.c
val gets : in_channel -> Bytes.t -> int -> int -> int
gets ic buf pos max gets a line from
ic and puts it at
buf. Number of bytes read is returned. If 0 bytes are read, then
ic is at end of file. Line length is limited to
max bytes if no newline is found. The newline is included in the line if a newline is found.