string

mailx(1) commands try to prevent this by issuing "Please specify a recipient" or "No
recipients specified" messages instead. If there is at least one valid recipient, each
invalid recipient address will generate a "User unknown" message.
Action
Look in the sender’s dead.letter file for the automatically saved message, and
have the originator send it again, this time specifying a recipient.
See Also
For more information about sendmail(1M), see the Mail Administration Guide.
Reset tty pgrp from int to int
Cause
The C shell sometimes issues this message when it clears away the window process
group after the user exits the window system. This can happen when the window
system doesn’t clean up after itself.
Action
Proceed with your work. This message is only informational.
Resource temporarily unavailable
Cause
This indicates that the fork(2) system call failed because the system’s process table
is full, or that a system call failed because of insufficient memory or swap space. It is
also possible that a user is not allowed to create any more processes.
Action
Simply waiting often gives the system time to free resources. However if this
message occurs often on a system, reconfigure the kernel and allow more processes.
Alphabetical Message Listing 161