To incorporate a previously edited file into the message, issue
~ r filenamewhere filename is the name of an ASCII file to be incorporated in the body of the message. The tilde MUST be the first character of the line.
If filename is not an ASCII file, use uuencode to encode it into an ASCII sequence.
Note that this must be done while writing the message. Here is a short mail session:
prompt> mail cantin
Subject:
the file course.tex will appear following this line
~ r course.tex
"course.tex" 80/1888
notice that the name of the file, its number of lines, and the size of it (in bytes) were displayed by the utility, not myself.
The dot on the next line indicates the end of the message.
.
Cc: stan