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12
votes
2answers
403 views

What does CTRL+4 (and CTRL+\) do in bash?

I just found out by accident that CTRL + 4 closes programs reading stdin input from the command-line. This is how it looks when I type CTRL + 4 or CTRL + / into programs reading stdin ryvnf:~$ ...
0
votes
2answers
25 views

Putting a single quote in a filename [duplicate]

We can a make a directory named $"dollars"&<>\dogs if we surround it with single quotes like the following mkdir '$"dollars"&<>\dogs' However, what if I want to include a ...
2
votes
2answers
53 views

What other special characters are there?

For filenames, I know that you have to use either a double quotes or a backslash to include a space in your file name. Like mkdir "I like coffee" is the same as mkdir I\ like\ coffee Now when you ...
1
vote
2answers
63 views

How tp Print/echo arrow key in unix - bash, version 3.2.52

How do I print ↑ and ↓ in Unix? Basically I have a script written in bash and I am printing some numbers with whom I want to print arrow keys to show increase/decrease. So how do I literally print ...
2
votes
2answers
273 views

Search and replace control characters (^@, ^M, ^I…) in vi

I copied this line from /proc/some_proc_id/cmdline in my ubuntu machine, java^@-jar^@/usr/lib/selenium/selenium-server-standalone.jar^@-port^@4444^@-trustAllSSLCertificates^@ Somehow, the space ...
2
votes
3answers
64 views

Garbage in bash session log file. (using script command)

I tried to log bash session using: js:/var/tmp # script -aqf /var/tmp/out In out file I see, besides output, a lot of garbage. Instead of just whitespaces and new lines I see this, for example: ...
1
vote
3answers
32 views

Order of text jumbled when printing

We run an automated process which changes the data structure in a file, and it has run for about a year without any issues. It has just started failing and I have narrowed the problem down to one of ...
1
vote
1answer
65 views

TTY control characters sent to stdin of sh doesn't work

I tried to develop a remote app that launches sh and resends an incoming data there, and found that some special sequences don't work. So, for testing purposes, I launched on my desktop sh, then ...
3
votes
2answers
107 views

How to skip special / socket files during rsync transfer?

Using the following command. rsync --archive --delete --partial --progress --recursive --no-links --no-devices --quiet source target Using --no-links and --no-devices already. Getting the error ...
20
votes
5answers
984 views

How can I find the common name for a particular glyph?

Sometimes, I'd like to know the name of a glyph. For example, if I see −, I may want to know if it's a hyphen -, an en-dash –, an em-dash —, or a minus symbol −. Is there a way that I can copy-paste ...
0
votes
2answers
40 views

non-breaking space sometimes appears in Geany (my standard text editor)

I use Geany for all my coding, in my linux Mint-MATE install. Occasionally, i have a problem where a non-breaking space (char code 194) is present instead of a normal space character (32). This just ...
0
votes
3answers
868 views

Remove special characters in a text file

I have a text file which contains in each line a sql query. For each line, I need to remove some special characters. Expl: if I have: select * from Users; insert into Users values ...
1
vote
5answers
74 views

keep out line break

I have some files with this structure: 2015-03-25 17:08:17 sysUpTimeInstance 93474;^M 1.ValueforState=2500 I want to replace the line break, and leave the third line with the second line, I mean, ...
5
votes
1answer
148 views

using ! character in echo

I am messing with echo and having issues with echo displaying the ! character. I tried this. echo -e "Wake!\nUp! bash: !\n!: event not found Then this # echo "Wake\!\nUp!" Wake\! Up! Well now ...
0
votes
2answers
168 views

Why can't I kill the shell using the PID obtained from the $$ special variable? [duplicate]

After I have learned that the $$ special variable holds the process number of the shell, I tried too kill the shell by simply: kill , however this did not work, I also tried some variations, but them ...
1
vote
2answers
230 views

Remove control characters from /var/log/boot.log

I have a script that sends out email to sysadmin group when a server is powered on or off. The email contains dump of some important logs like /var/log/messages, /var/log/secure, /var/log/boot.log . ...
5
votes
1answer
120 views

Representing/quoting NUL on the command line

Can \0 be used on the command line? Background For testing corner cases in GNU Parallel I was curious whether all characters were correctly quoted on the command line. Most of them are: perl -e ...
26
votes
8answers
2k views

Dealing with file names with special first characters (ex. ♫)

I have recently come across a file whose name begins with the character '♫'. I wanted to copy this file, feed it into ffmpeg, and reference it in various other ways in the terminal. I usually ...
0
votes
2answers
203 views

How to printf an exclamation point in tcsh?

What's the best way to printf an exclamation point in tcsh? It seems like using single or double quotes has no effect on escaping the exclamation point; and using a backspace does work, but then it ...
4
votes
2answers
522 views

How can I write a non-breaking space? [closed]

When I write a question, I'd like the space between the final word and the question mark to be non-breaking, and this very sentence is an example of it (this is why it is awkward), how can I do that ? ...
6
votes
2answers
209 views

How many commands can be queued up with control operators?

I have been reading up on control operators, and I was wondering if there was a limit to how many commands you could line up with control operators, such as ||, && and ;. In addition, is ...
-1
votes
0answers
22 views

replace $ with £ using sed command [duplicate]

I have text file DollarToPound.txt with some Dollar signs ($) please provide a shell script to replace dollar symbol with Pound(£) with sed command. iam getting command garbled error!!! please help. ...
1
vote
1answer
82 views

Forcing the system to allow me to insert any character in the file name

I had an exam this week, and one of the questions was (with one correct answer): The file name can contain the character: a) \ b) / c) ? d) ! I chose c) ? because it looked ...
1
vote
2answers
540 views

printing special characters in awk output

I have a large file that contains lot MQ messages with RFH2 header. Each message in the file is separated by a blank line. Now I need to split this large file into small files each containing single ...
2
votes
1answer
268 views

csplit not obeying backslash r \r as carriage return

I have a file with \r\n line endings (CRLF carriage return line feed). This command works: $ csplit --silent --prefix=email-emailbad.txt- \ --digits=3 emailbad.txt '/^\.^M/'+1 '{*}' This ...
2
votes
1answer
248 views

What is the ` character or symbol called and what is its significance outside of SE code formatting? [duplicate]

What is the ` character's name and what is its significance outside of SE code formatting because I cannot get it to work? I'm familiar with its use in the Stack Exchange forums used to format code ...
11
votes
7answers
3k views

What is the symbol *.* called?

What's the name for the *.* symbol and what is its significance?
2
votes
2answers
403 views

How to rename filename with ' or ? in file name?

I have a problem renaming a file that I'm not even sure which special characters I have in the file. I'm using CentOS 6 64bit. When I ls the file: Giko Suzo San?e - Ep1.avi but when view it in ...
2
votes
2answers
198 views

Very strange ls > textfile problem when viewing with emacs

I want to list the components of the current working directory in a text file ls -1 > textfile Output looks fine with more. 1010661085645 1010729039145 1010747080245 1010849051345 ...
1
vote
1answer
713 views

Sed: search and replace a patten with special characters which has a arbitrary string in between

I have a load of nfo files which I want to make some global substitutions for some values within each file e.g. a.nfo has the value <set>Tonight&apos;s Menu ( June 2012 )</set> ...
2
votes
2answers
604 views

delete directory with special character in filename

I have these tricky directories that I can't figure out how to delete. If I run ls -ld * I get… drwxrwxr-x 7 user1 taskfmri 2048 Jan 22 15:26 857263 drwxrwx--- 4 user2 ...
4
votes
3answers
2k views

Help Shell script to pass variables to rsync

I'm trying to create a simple wrapper shell script for rsync. When I send file names to my script, rsync can never seem to identify the correct location. The file names have spaces in them. I've tried ...
4
votes
5answers
1k views

What are the special characters to print from a script to move the cursor?

I found that by printing \r from a script the cursor moves to the beginning of the line. What character will move the cursor up one line? Where is a list of these special characters? EDIT: Working ...
1
vote
1answer
124 views

What's the practical difference between `command` and $(command)? [duplicate]

Both give the output of the command, so what is the semantic difference between the two? Some reading led me to suspect is that $(command) is Bash syntax, and the back quotes are integrated into Unix ...
-1
votes
2answers
299 views

How can I force sed to continue parsing when it hits an “invalid” character?

I have a big playlist in .pls format (created with deadbeef playing software) which also contains some badly-encoded strings. Whether this is a bug in deadbeef or one of its plugins does not really ...
2
votes
1answer
261 views

What characters TAR doesn't like?

I keep a list of photos burned to dvds for incremental backups but I got into a strange situation where a file was already burned into a dvd but tar keeps saying it's not. Here the steps to reproduce: ...
2
votes
1answer
1k views

Double line box_drawing characters in terminal

This piece of code in wikipedia: $ char=( 6a 6b 6c 6d 6e 71 74 75 76 77 78 ) $ for i in ${char[*]}; do printf "0x$i \x$i \e(0\x$i\e(B\n"; done includes one-line box-drawing characters. Are there ...
7
votes
4answers
6k views

How to grep for pipe |

How can I grep for line containing pipe character | or for character >: files content: |this is test where is > this is none now what I need using grep command is grep -iE "<some ...
0
votes
3answers
201 views

How to delete directory ' :q!'? [duplicate]

Accidentally, i have got this directory created in my home, drwxr-xr-x 2 ubuntu ubuntu 4.0K 2012-09-06 07:27 :q!/ I want to remove this somehow. I have tried using escape characters in double ...
2
votes
4answers
5k views

sh and grep numbers only

I'm facing a problem and trying to find a solution that works in sh. If I could use bash this code would work: ls /a|grep ^[0-9] Unfortunately this is not the case with sh, and yes I need to use ...
5
votes
2answers
6k views

What does the tilde (~) mean at the end of a filename? [duplicate]

What is the file with the ~ at the end of the filename for? $ ls # aliased to add flags -rwxrwxr-x 1 durrantm 2741 May 16 09:28 strip_out_rspec_prep_cmds.sh~* drwxrwxr-x 13 durrantm 4096 May 16 ...
58
votes
7answers
4k views

How safe is it to cat an arbitrary file?

Sometimes when I cat a binary file by mistake, my terminal gets garbled up. Nothing a quick reset can't fix, but couldn't an attacker theoretically create a file that, when displayed on a terminal, ...
1
vote
1answer
1k views

tr command not working with octal sequences

I need to strip non-ASCII characters off a file. I was using the command - /usr/xpg4/bin/tr -cd '\0-\177' <non-ASCII_file.dat >ASCII_file.dat Though it worked in the past, it is not ...
0
votes
1answer
66 views

What characters in my printed boot scroll are artifacts?

I am a tech writer and I need to include a boot dump in a document. The dump the engineers gave me has some "bad characters" that I need to delete. What form does a "bad character" take? There are ...
2
votes
1answer
296 views

tcsh vs zsh. Escape/control characters

I am having problems running this command to work in zsh: my_command -u something -s X:^0 The command works right away on tcsh, but on zsh I get: zsh: no matches found -s X:^0 This made me ...
3
votes
2answers
496 views

Hash symbol on a teletype

My issue is a bit unusual, so I want to provide a short background. I was looking at old winners of the International Obfucated C Code Contest, and came across an entry written for the PDP-11 (the ...
2
votes
1answer
4k views

sed special character replace not working in shell script

I want to write a script 'test.sh' that will take a user's input and replace all special characters with a '\' + the character. My script: #!/bin/bash echo 'input='"$1" arg=`echo "$1" | sed ...
8
votes
2answers
517 views

Command line input while a running script displays strange symbols

If I use the bash shell cli and run some program which doesn't return immediately, then I input some letters (basically typing the next command before noticing the previous didn't finish) and the ...
2
votes
1answer
280 views

Control character STTY issue

I am changing control character (e.g- ^C) using stty intr ^_ under root privileges. It changes successfully. But when I am closing terminal and opening terminal again to check whether same ...
0
votes
1answer
307 views

Checking existence of file with underscore in file name in zsh

I am writing a very simple script which will link shared configuration files. For some reason it does not behave as i expected for file with underscore in name. Does _ (underscore) means something ...