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Questions tagged [control-characters]

a code point (a number) in a character set, that does not represent a written symbol.

In computing and telecommunication, a control character or non-printing character is a code point (a number) in a character set, that does not represent a written symbol.

Control character - Wikipedia

23 questions
31
votes
2 answers

Notepad Ctrl-Backspace behavior

Text fields in almost all software erase a word when ctrl+backspace is pressed. However, Notepad behaves differently, and inserts a character which is: `` (I copy-pasted it here. I'm not sure if it is visible. It looks like a rectangle in…
musa
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13
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5 answers

Why is backspace often represented with ^H?

I don't see what ^H has in common with "backspace". Why is backspace represented that way in many locations?
Billy ONeal
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12
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3 answers

What do the first 32 characters of the ascii table do?

The first 32 characters of the ASCII table (0x00 - 0x1F) are all of the non-printable characters (with the exception of 'DEL' which comes at the end of the table). What are these used for, other than borking your terminal when you cat a binary…
Barton Chittenden
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7
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5 answers

gVim control characters on Windows

I copied some data from an app and it has lots of ^Ds and ^Ms in it. I got rid of ^D with no problem using :%s/^D//g and I know I can remove ^M with something like :%s/^V^M//g but the problem is that I'm running on windows and ^V is Ctrl-V, which…
FrustratedWithFormsDesigner
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6
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2 answers

What's the difference between ^S and ^Z inside a terminal?

When using a terminal emulator, one can stop the currently running program with either CTRL-Z or CTRL-S. What's the difference between these control characters?
Eugene Yarmash
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5
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1 answer

How to show CR in Geany

Can Geany be switched into a mode where it displays CR characters (but not LF characters)? Can Geany be forced to only wrap a line on LF but not on CR? Generally speaking: Geany wraps a line on all three possible forms of a line ending: a single CR,…
Tino
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5
votes
3 answers

Create a flat file where control characters have been interpreted in Debian

I like to use the 'script' command to record console sessions. The problem is that the 'typescript' file which is created contains control chars (when using arrows or the delete key). Apart from editing the file manually, is there a way to generate…
Gra
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2
votes
2 answers

How to remove three consecutive line feeds in a Makefile rule?

I need to search for and replace three consecutive newline characters in an input file and filter them out of an output file for a makefile rule on Centos 4. I am using GNU sed v4.1.2 and GNU make v3.82. I've tried variations on the following with…
WilliamKF
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1
vote
1 answer

I can't replace line breaks in vim and iterm

In Vim in iTerm, I frequently encounter issues surrounding line breaks. For example, if I have a file containing the dreaded ^M most online tutorials will say that to perform a replacement I use a regular find and replace on a file…
clumsyjedi
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1
vote
1 answer

NUL characters plus Notepad++ equals monitor squel?

Whenever I open a file that contains NUL characters in Notepad++ my monitor starts to emit high pitched, squealing kind of noise. It doesn't always do that. There is certain criteria to be fulfilled. It largely depends on how many they are, and also…
Samir
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How to make ^T work for the status char under Linux?

I’ve grown really accustomed to the BSD status char, ^T, since I first started using it back at university during the 80s. It didn’t originate with BSD, but came from even older operating systems. It still works on modern BSD systems, too,…
tchrist
  • 218
1
vote
1 answer

Bash prompt with zero width control characters

To prevent the prompt from warping around right-to-left text, I want to insert a zero width LRM into the bash prompt (U200e). Since this is a zero width character, my instinct was to wrap it with \[<200e>\]. Turns out, that actually causes bash to…
Shachar Shemesh
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0 answers

Python hangs when printing some Unicode c1 control characters, not in a consistent manner

For testing purposes, I created a file with bytes 0xc2 0x90, representing Unicode code point 0x90 in UTF-8 encoding. I can cat this file without an issue, but trying to print the string written from it, or the corresponding literal, or the string…
Karl Knechtel
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1
vote
2 answers

Type superscripts of multiple characters to express mathematical exponents

If in linux I type CTRL-shift-U, followed by a unicode control code, I can type a superscript. So if I type 10, followed by CTRL-shift-U, followed by b9, I can get 10¹. How though do I write something like 10 to the power of 18?
markling
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1
vote
2 answers

Has anyone seen the output of the "net time" command display odd characters?

I've started seeing this on numerous Windows 10 systems, including my work and home PCs. Essentially, the time output of the NET TIME \\LOCALHOST command, which usually looks like "Current time at \\localhost is 4/2/2020 12:11:15 PM" now contains…
Steven P
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