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^U will clear the buffer - super convenient for retrying botched passwords.
As a corollary, typing ^D twice on a non-empty line will also send EOF on the input, allowing you to provide a program with input not ending with \n from the command line. I knew about this behavior, but not why it worked, but this article's explanation clarifies this behavior as well. The first ^D terminates the read() call, passing the line so far, without terminating \n, to the program. The second causes read() to…
I know this article says Unix specifically, but on Linux (Ubuntu) I just tried typing `ls^D` in bash and got a terminal beep. I tried in zsh and got an autocomplete as if I'd hit tab. In ksh and fish nothing happened. I'm curious as to why there are different behaviors here?
Earlier quoted context omitted.
I know this article says Unix specifically, but on Linux (Ubuntu) I just tried typing `ls^D` in bash and got a terminal beep. I tried in zsh and got an autocomplete as if I'd hit tab. In ksh and fish nothing happened. I'm curious as to why there are different behaviors here?
As the article explained at the end, shells put the terminal into uninterpreted mode, so ^D doesn't do anything special there. You have to be using a program (such as cat) that doesn't do this to see ^D's behavior.
However, you can write a shell that doesn't do this. In particular, on Linux, you can experiment in dash. You'll find that the behavior is exactly the same as this article, since the terminal remains in cooked mode. In particular, if you type `l^Ds`, that will run `ls`, though you won't be able to delete the `l` anymore since that was input before the `^D`. Also, if you type `ls^D^D`, that will log out just like typing `^D` on an empty line does. Other shells have different behaviors -- for example, Bash seems to take `ls^D` to be the same as typing `ls` followed by pressing Enter.
Before any shell starts executing a program, however, it puts the terminal back in cooked mode no matter what mode it's in when at the prompt, since that's the default terminal mode expected by programs. If you want to experiment with the cooked mode line editing commands to get the behavior described in the article, you should run a command that receives standard input from the terminal (running `cat` by itself should suffice).
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^Y will paste the cleared buffer back again
So ^U will let a partial password linger in memory longer than it needs to if you use it as suggested by the GP?
You can test this yourself. Type some text, then ^U, then ^Y. This works because your shell uses libreadline or libeditline. Try this again in a "dumb" program like cat, or a shell without line editing like /bin/dash. ^U works, but ^Y does nothing (well, it lets you type ^Y in as much as you want).
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^L usually has no assigned action. $ stty -a | grep -F '^D' intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = ; $ stty -a | grep -F '^L' $ Your Ctrl-L clear-and-refresh command is implemented in Bash (or rather GNU readline). There is a "reprint" action, commonly bound to ^R: $ stty -a | grep rprnt eol2 = ; swtch = ; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; It doesn't clear the screen; it just issues…
And sadly ^t doesn't do the Tenex function of a snapshot of sysstat for the current process.
Earlier quoted context omitted.
^L usually has no assigned action. $ stty -a | grep -F '^D' intr = ^C; quit = ^\; erase = ^?; kill = ^U; eof = ^D; eol = ; $ stty -a | grep -F '^L' $ Your Ctrl-L clear-and-refresh command is implemented in Bash (or rather GNU readline). There is a "reprint" action, commonly bound to ^R: $ stty -a | grep rprnt eol2 = ; swtch = ; start = ^Q; stop = ^S; susp = ^Z; rprnt = ^R; It doesn't clear the screen; it just issues…
And sadly ^t doesn't do the Tenex function of a snapshot of sysstat for the current process.
For reference it means Ctrl+D, unless you you have a strange keyboard from Sun or something.
^U will clear the buffer - super convenient for retrying botched passwords.
In readline, ^U will only clear from the cursor to the start of the line, leaving anything on the right. ^K is the converse. I'm not sure you are speaking about readline though. Another very useful thing I use daily is Alt-F/B, to move forward/backward in the line one word at a time. Control does the same, one letter at a time. D will delete an element instead.
Ctrl-L to clear the screen except the current line is also somewhat useful if you're at the bottom of the terminal screen and editing a long command line.
Somewhat less useful but neat is Alt-U which will cause the current word under the cursor to become all upper case and Alt-C which is similar but changes the first letter to upper case and the rest of the word to lower case.
^U will clear the buffer - super convenient for retrying botched passwords.
In readline, ^U will only clear from the cursor to the start of the line, leaving anything on the right. ^K is the converse. I'm not sure you are speaking about readline though. Another very useful thing I use daily is Alt-F/B, to move forward/backward in the line one word at a time. Control does the same, one letter at a time. D will delete an element instead.
Personal favorites are C-r to search back in history and C-x C-e to edit the current command line in an external editor.