--- layout: post title: Stty and rlwrap on Linux category : Linux tags : [Linux, Utilities] --- ## 退格键 在Linux环境下，使用`SQL*Plus`时有时会出现退格键不好使用的情况。此时，可以一般可用使用stty命令来解决。 stty(set tty，设置tty)命令用于检查和修改当前注册的终端的通信参数。UNIX系统为键盘的输入和终端的输出提供了重要的控制手段，可以通过stty命令对特定终端或通信线路设置选项。该命令可以改变并打印终端行设置。 看这个命令的帮助： [oracle@dev ~]$ stty --help Usage: stty [-F DEVICE] [--file=DEVICE] [SETTING]... or: stty [-F DEVICE] [--file=DEVICE] [-a|--all] or: stty [-F DEVICE] [--file=DEVICE] [-g|--save] Print or change terminal characteristics. -a, --all print all current settings in human-readable form -g, --save print all current settings in a stty-readable form -F, --file=DEVICE open and use the specified DEVICE instead of stdin --help display this help and exit --version output version information and exit Optional - before SETTING indicates negation. An * marks non-POSIX settings. The underlying system defines which settings are available. Special characters: * dsusp CHAR CHAR will send a terminal stop signal once input flushed eof CHAR CHAR will send an end of file (terminate the input) eol CHAR CHAR will end the line * eol2 CHAR alternate CHAR for ending the line erase CHAR CHAR will erase the last character typed intr CHAR CHAR will send an interrupt signal kill CHAR CHAR will erase the current line * lnext CHAR CHAR will enter the next character quoted quit CHAR CHAR will send a quit signal * rprnt CHAR CHAR will redraw the current line start CHAR CHAR will restart the output after stopping it stop CHAR CHAR will stop the output susp CHAR CHAR will send a terminal stop signal * swtch CHAR CHAR will switch to a different shell layer * werase CHAR CHAR will erase the last word typed Special settings: N set the input and output speeds to N bauds * cols N tell the kernel that the terminal has N columns * columns N same as cols N ispeed N set the input speed to N * line N use line discipline N min N with -icanon, set N characters minimum for a completed read ospeed N set the output speed to N * rows N tell the kernel that the terminal has N rows * size print the number of rows and columns according to the kernel speed print the terminal speed time N with -icanon, set read timeout of N tenths of a second …… Handle the tty line connected to standard input. Without arguments, prints baud rate, line discipline, and deviations from stty sane. In settings, CHAR is taken literally, or coded as in ^c, 0x37, 0177 or 127; special values ^- or undef used to disable special characters. Report bugs to . 与退格键相关的设置是erase，它表示删除最后一个字符。 $stty erase ^H 说明：按下退格键会显示成^H。 如果在当前窗口执行的话，只对当前的窗口有效，下次登陆的时候还需要重新设置，可以把这个命令写入shell 的配置文件，如`~/.bashrc` 中，这样每次都能生效了。 ## 方向键 Windows下使用方向键是没有问题的，但是在Linux下，方向键是使用不了。此时可以安装一下rlwrap工具。 SQL> ^[[A ----[按方向键会显示异常] rlwrap本身是个遵循GPL 标准的Shell 脚本，可以运行任何你提供给它的命令包括参数，并添加命令历史浏览功能。 1) 关于rlwrap [root@dev ~]# yum info rlwrap Loaded plugins: fastestmirror, refresh-packagekit, security Determining fastest mirrors base | 1.3 kB 00:00 extras | 1.3 kB 00:00 Installed Packages Name : rlwrap Arch : x86_64 Version : 0.37 Release : 1.el6 Size : 196 k Repo : installed From repo : extras Summary : Wrapper for GNU readline URL : http://utopia.knoware.nl/~hlub/rlwrap/ License : GPLv2+ Description : rlwrap is a 'readline wrapper' that uses the GNU readline library to : allow the editing of keyboard input for any other command. Input : history is remembered across invocations, separately for each command; : history completion and search work as in bash and completion word : lists can be specified on the command line. 2) 安装rlwrap [root@dev soft]# yum install -y rlwrap 3) 测试 [oracle@dev ~]$ rlwrap sqlplus / as sysdba SQL*Plus: Release 10.2.0.1.0 - Production on Wed Jun 27 17:42:50 2012 Copyright (c) 1982, 2005, Oracle. All rights reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production With the Partitioning, OLAP and Data Mining options SQL> select * from v$version; BANNER ---------------------------------------------------------------- Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod PL/SQL Release 10.2.0.1.0 - Production CORE 10.2.0.1.0 Production TNS for Linux: Version 10.2.0.1.0 - Production NLSRTL Version 10.2.0.1.0 - Production SQL> select * from v$version; --[按方向键可用正常输入] 现在就可以上下翻动了。 4) 设置别名 但是这样没事都需要加上rlwrap 也是很麻烦的，可以对rlwrap 做一个别名，放到shell 的配置文件里，在`~/.bashrc` 文件里添加如下内容： alias sqlplus='rlwrap sqlplus' 5) 让参数生效 [oracle@dev ~]$ source ~/.bashrc 6) 测试 [oracle@dev ~]$ type sqlplus sqlplus is aliased to `rlwrap sqlplus' [oracle@dev ~]$ $ sqlplus / as sysdba SQL*Plus: Release 10.2.0.1.0 - Production on Wed Jun 27 17:42:50 2012 Copyright (c) 1982, 2005, Oracle. All rights reserved. Connected to: Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production With the Partitioning, OLAP and Data Mining options SQL> select * from v$version; BANNER ---------------------------------------------------------------- Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Prod PL/SQL Release 10.2.0.1.0 - Production CORE 10.2.0.1.0 Production TNS for Linux: Version 10.2.0.1.0 - Production NLSRTL Version 10.2.0.1.0 - Production SQL> select * from v$version; --[按方向键可用正常输入] 其他一些组合键： Ctrl+A：ahead，到行的顶端，相当于 Home Ctrl+E：end，到行的末端，相当于end Ctrl+B：behind，后退一个字符，相当于left Ctrl+F：forward，前进一个子放入，相当于right Ctrl+P：prev.，上一行历史记录，相当于up Ctrl+N：next.，下一行历史记录，相当于down Ctrl+U：undo，回复操作，这行就被清空掉了 Ctrl+W：剪切 Ctrl+Y：粘贴 Ctrl+L：cLear，清屏 ## 参考 * [Linux下`SQL*Plus`退格、方向键问题](http://blog.csdn.net/tianlesoftware/article/details/6168219) * [利用Uniread解决Linux下的`SQL*Plus`命令历史回调功能](http://dbanotes.net/tech-memo/uniread-howto.html) * [Another tool for ‘Command Line History’](http://dbanotes.net/database/another_tool_for_command_line_history.html#more-99)