IBM 3270 Manual page 57

Your default drive will change to the fixed
disk:
7. Type the SEND command next to the DOS
ready message.
For example:
C>send a:pcfile.txt e:cmsfile script a1 (ascii crlf)
This command sends a file named
PCFILE. TXT from a diskette in your A drive
to the A-disk on your VM host in a host
window named E.
• If you do not have a file named CMSFILE
SCRIPT on your A-disk, PCFILE. TXT will
be added to your A-disk with the name
CMSFILE and a type SCRIPT. The length
of all the records in CMSFILE will be
fixed at 80 characters.
• If you have a file named CMSFILE
SCRIPT on your A-disk, PCFILE.TXT will
replace the CMSFILE on your A-disk.
Everything that was in it will go away.
Note: This example illustrates only one form
of the SEND command. It may work
for you, or it may not. The next section
and the examples explain how you can
write other versions of the SEND
command that you may need.
7-4 Book 3 - Using the Control Program