termio.7 (2010 09)
t
termio(7) termio(7)
waiting, (that is, the EOF occurred at the beginning of a line) a character count of
zero is returned from read(), representing an end-of-file indication. If
ICANON is
enabled, the EOF character is discarded when processed. If
ICANON is not enabled,
the EOF character is treated as a normal data character.
NL (ASCII LF) special character on input and is recognized if
ICANON flag is enabled. It
is the line delimiter (
\n). If
ICANON is not enabled, the NL character is treated as a
normal data character.
EOL (ASCII NUL) special character on input and is recognized if
ICANON is enabled.
EOL is an additional line delimiter similar to NL. It is not normally used. If
ICANON is not enabled, the EOL character is treated as a normal data character.
EOL2 (disabled) special character on input and is recognized if
ICANON is enabled. EOL2
is an additional line delimiter similar to EOL. It is not normally used. If
ICANON is
not enabled, the EOL2 character is treated as a normal data character.
SUSP (disabled) special character recognized on input. If
ISIG is enabled, receipt of the
SUSP character causes a
SIGTSTP signal to be sent to all processes in the fore-
ground process group for which the terminal is the controlling terminal, and the
SUSP character is discarded when processed. If ISIG
is not enabled, the SUSP
character is treated as a normal data character. Command interpreter processes typi-
cally set SUSP to Control-Z.
DSUSP (disabled) special character recognized on input. If
ISIG is enabled, and a process in
the foreground process group attempts to read the DSUSP character, a SIGTSTP sig-
nal is sent to all processes in the foreground process group for which the terminal is
the controlling terminal, and the DSUSP character is then discarded. If ISIG is not
enabled, the DSUSP character is treated as a normal data character. Note that
DSUSP is similar to SUSP except that the signal is sent when a process in the fore-
ground process group attempts to read the DSUSP character, rather than when it is
typed.
STOP (Control-S or ASCII DC3) special character on both input and output. If
IXON (out-
put control) is enabled, processing of the STOP character temporarily suspends output
to the terminal device. This is useful with CRT terminals to prevent output from
disappearing before it can be read. While output is suspended and IXON is enabled,
STOP characters are ignored and not read. If IXON is enabled, the STOP character
is discarded when processed. If IXON is not enabled, the STOP character is treated
as a normal data character. If IXOFF (input control) is enabled, the system sends a
STOP character to the terminal device when the number of unread characters in the
input queue is approaching a system specified limit. This is an attempt to prevent
this buffer from overflowing by telling the terminal device to stop sending data.
START (Control-Q or ASCII DC1) special character on both input and output. If
IXON (out-
put control) is enabled, processing of the START character resumes output that has
been suspended. While output is not suspended and
IXON is enabled, START char-
acters are ignored and not read. If IXON is enabled, the START character is dis-
carded when processed. If IXON is not enabled, the START character is treated as a
normal data character. If IXOFF (input control) is enabled, the system sends a
START character to the terminal device when the input queue has drained to a cer-
tain system-defined level. This occurs when the input queue is no longer in danger of
possibly overflowing.
CR (ASCII CR) special character on input is recognized if
ICANON is enabled. When
ICANON and ICRNL are enabled and IGNCR is not enabled, this character is
translated into a NL, and has the same affect as the NL character. If ICANON and
IGNCR are enabled, the CR character is ignored. If ICANON is enabled and both
ICRNL and IGNCR are not enabled, the CR character is treated as a normal data
character.
LNEXT (disabled) special character recognized on input. Causes the special meaning of the
next character to be ignored. This works for all special characters specified above. It
allows characters to be input that would otherwise be interpreted by the system for a
special function.
HP-UX 11i Version 3: September 2010 − 5 − Hewlett-Packard Company 5