Questions tagged [control-characters]
Use this tag for questions about control characters – non-printing characters used to send signals to the output terminal.
30 questions
1
vote
1
answer
237
views
What is PS1 prompt \[\e]0; vs \[\e]2; , it looks like one is for title name of tab, one is for title name of windows
here is my ps1
does someone know documents about this?
export PS1='\[\e]0;YYY@\h:\w\a\]\[\e]2;XXX\W\a\e[32;40m\]\[\e[36;40m\]$?\[\e[31;40m\]\D{%d}\[\e[35;40m\]\D{%H%M}\[\e[36;40m\]\W\[\e[32;40m\]>\[...
0
votes
2
answers
202
views
Difference between non-graphic characters and non-printable characters
My system:
Ubuntu 22.04.3 LTS
GNU bash, version 5.1.16(1)-release (x86_64-pc-linux-gnu)
man ls describes -b as follows:
-b, --escape
print C-style escapes for nongraphic characters
The ...
0
votes
0
answers
76
views
Binary file with field seperator ^A is not loading using SQLLDR
I'm trying to upload .dat file to Oracle DB using SQLLDR.
File data columns are separated by "^A".
File charset is of binary.
bash-4.4$ file -i /tmp/t_details_all_data_20240209.dat
/tmp/...
2
votes
0
answers
40
views
Apply control charactes to file reddirect
Tried various existing answers, but didn't find any which entirely works. This is one line example, and show how it fails, maybe some extra switch or step can solve this?
This is the content of file I ...
1
vote
3
answers
407
views
Where are the characters going?
In a shell where \u is valid (bash +4.3, ksh93 or zsh) we can print Unicode characters:
$ printf 'a b c \ua0 \ua1 \ua2 \ua3 \n'
a b c ¡ ¢ £
Which are some characters from the Latin-1_Supplement ...
1
vote
2
answers
435
views
color codes messing up table formatting of printf to xterm
My script-in-progress displays a multi-column colorized table, but the color-codes are interfering with the formatting. The color codes cannot be moved to the format string because the coloring of ...
1
vote
1
answer
1k
views
xterm does not support osc 52
I use xterm that comes with XQuartz on my macbook. However OSC 52 control sequence doesn't seem to work. Here's how to repro:
open xterm
in the shell, issue printf '\e]52;c;%s\007' $(printf 'test off'...
13
votes
1
answer
2k
views
Why do ^M and \r behave inconsistently?
Perhaps there are already answers out there that indirectly answer my question, but I've read many of them and haven't yet found a satisfactory answer to this discrepancy.
The original meaning of ...
3
votes
1
answer
543
views
What can the C1 control codes be used for?
Today I discovered that there is a significantly large group of additional control codes, called C1 control codes, spanning from U+0080—U+009F (32 characters). I think that it's an interesting fact ...
0
votes
0
answers
327
views
Control characters in bash history scramble subsequent lines
Sometimes, when I invoke history in bash, it starts printing normally, and at some point switches to garbled characters:
Oddly, when I copy that from my terminal and paste it here, the characters are ...
7
votes
1
answer
939
views
gnome-terminal: strange control characters on Alt key
I probably misconfigured something, but I don't know what. (see UPDATE 1 and 2 below) In gnome-terminal, when I hit Alt (without any other key), it immediately sends ^[< to the terminal (I tested ...
2
votes
2
answers
2k
views
How can I change CMD to CTRL in Linux Mint only in Terminal?
I installed Linux Mint on my MacBook Air, and I prefer to use Cmd for copying/pasting, opening and closing windows, and general things like that. However, I would like to use Ctrl to input to the ...
1
vote
0
answers
579
views
Why are rapid Ctrl-Space sequences sometimes handled differently by GNU screen than slow Ctrl-Space?
I have GNU screen configured to use Ctrl+Space as the escape character. This means that Ctrl+SpaceSpace will send a literal Ctrl+Space to the process in the window. Also, Ctrl+Space Ctrl+Space is the ...
0
votes
2
answers
163
views
How to dynamically look up shell variable name [duplicate]
I have this situation:
zmx_stderr='\033[1;35m'
zmx_stdout='\033[1;36m'
tag='foobar'
tailing(){
echo "tailing logs for ${tag} ...";
while read line; do
echo -e "$zmx_${1} $tag $1${zmx_no_color}...
5
votes
1
answer
7k
views
`cat -v` for non-printing non-ascii UTF characters
cat has a -v option which converts non-printing characters to their caret notation (which is useful if we don't want the terminal to interpret the control characters literally in cat output).
But ...