### 3.1.5 Editing input

The following keys can be used for editing the input and retrieving previous input lines:

`TAB`
  provides command line completion for function names and file names
`CTRL-B`
  moves cursor to the left
`CTRL-F`
  moves cursor to the right
`CTRL-A`
  moves cursor to the beginning of the line
`CTRL-E`
  moves cursor to the end of the line
`CTRL-D`
  deletes the character under the cursor
  Warning: on an empty line, `CTRL-D` is interpreted as the `EOF` character which immediately terminates SINGULAR.
`BACKSPACE`
`DELETE`
`CTRL-H`
  deletes the character before the cursor
`CTRL-K`
  kills from cursor to the end of the line
`CTRL-U`
  kills from cursor to the beginning of the line
`CTRL-N`
  saves the current line to history and gives the next line
`CTRL-P`
  saves the current line to history and gives the previous line
`RETURN`
  saves the current line to the history and sends it to the SINGULAR parser for interpretation

When run under a Unix-like operating system and in its ASCII-terminal user interface, SINGULAR tries to dynamically link at runtime with the GNU Readline library. See section `Command Line Editing' in The GNU Readline Library Manual, for more information. If a shared version of this library can be found on your machine, then additional command-line editing features like history completion are available. In particuliar, if SINGULAR is able to load that library and if the environment variable `SINGULARHIST` is set and has a name of a valid file as value, then the input history is stored across sessions using this file. Otherwise, i.e., if the environment variable `SINGULARHIST` is not set, then the history of the last inputs is only available for previous commands of the current session.

User manual for Singular version 4-0-3, 2016, generated by texi2html.