Asynchronous Terminals and Printer Processes Programming Manual

TERMINAL PROGRAMMING CONSIDERATIONS
System Resource and Hardware Problems
12, 16, 17, 19, 26, 27, 30, 31, 32, 33, 34, 35, 36, 37, 39,
120, 122, 123, 124, 137, 138, 139, 157, 160, 172, 173, 180,
190, 191, 192, 193
Some of these error numbers (such as 12, FILE IN USE) indicate
transitory problems. Others (such as 35, UNABLE TO OBTAIN I/O
PROCESS CONTROL BLOCK, or 138, INTERRUPT OVERRUN) could indicate
anything from a transitory problem to something more serious
requiring corrective action by your Tandem representative. In
any case, it is reasonable to respond to the above error numbers
by periodically retrying the I/O operation some specified number
of times.
Error 124 may occur if the CLIP has too little buffer space to
accept a request from the I/O process. If this happens, reduce
the CLB frame size that is specified in the configuration file.
Device Down or Link Down
The file-system error numbers 60, 66, and 100 indicate that the
device or communication link is down. Such situations cannot be
corrected by retrying the I/O operation. If an OPEN call fails
with error 100, there is an error in the configuration file.
Operation Timed Out_
Error 40 indicates that the terminal operator did not complete a
data entry within the time allotted by a call to AWAITIO. Data
entered before the timeout occurred is lost. You should send
a message instructing the terminal operator to reenter the most
recent data string.
Break Errors
Pressing the BREAK key on a terminal where BREAK is enabled can
cause an application process to receive either of two errors:
• Error 110--only break operations permitted
• Error 111--operation aborted because of break
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