This function causes a fetch of a particular section of the body of the specified messages as a text string and returns that text string. The section specification is a string of integers delimited by period which index into a body part list as per the IMAP4 specification. Body parts are not decoded by this function.
The options for imap_fetchbody() is a bitmask with one or more of the following:
FT_UID- The msg_number is a UID
FT_PEEK- Do not set the \Seen flag if not already set
FT_INTERNAL- The return string is in internal format, will not canonicalize to CRLF.
See also: imap_fetchstructure().