Question: I've been told that I need
to use the rlwrap utility with SQL*Plus. What is rlwrap and
how does it help me in SQL*Plus?
One nice features of using SQL*Plus in Windows is that you can use
"up arrow" and down arrow" keys to display the command line history
for all SQL*Plus commands.
It's also possible to do this in Linux and UNIX (AIX, Solaris,
HP/UX) with the freeware rlwrap utility.
freeware rlwrap utility at this link.
The readline wrapper (rlwrap) utility uses the GNU readline library.
Hence, rlwrap is not Oracle-centric, it's a standard OS utility
available for all flavors of UNIX, Linux and even Windows. The
rlwrap software installs easily on UNIX/Linux with these standard GNU unzip
and make commands:
tar -xvf rlwrap*.tar
Following the install, you use a standard UNIX alias in your
shell signon file (.cshrc for S shell, .bashrc for Bourne shell, or
.profile for Korn shell) to source-in the rlwrap utility, using a
different command name:
alias rl_asmcmd='rlwrap asmcmd'
Rampant author Laurent Schneider notes why you should never
use an alias over-ride of the default Oracle names of "sqlplus",
"asmcmd" or "rman":
Using rlwrap may affect the behavior of CTRL+C during
interactive sessions. I've done a few tests on this and I can't see
a difference in behavior of CTRL+C with or without rlwrap. Perhaps
this was a problem with earlier versions. Note that rlwrap only supports
interactive sessions, so scripts like the following may not work as
sqlplus alias: From
what I can see the alias doesn't seem to work from within a shell
script (bash, ksh or csh), so it doesn't really present a danger.
Remember, rlwrap is not an Oracle
tool! I guess it's best to leave the sqlplus and rman commands clean
and alias using a different name, just in case.
The rlwrap utility is a nice utility for command-line editing
and an easy display of SQL*Plus command history.
author Kamran Agayev Agamehdi shows how to install and use rlwrap on
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