I want to check if a shell variable contains an absolute path. I don't care if the path exists or not—if it doesn't I'm going to create it—but I do want to ensure that I'm dealing with an absolute pathname. My code looks something like the following: myfunction() { [ magic test to see if "$1" is an absolute path ] || return 1 mkdir -p "$(dirname "$1")" || return 1 commands >> "$1" } Or, the use case where the absolute path to be verified is intended to be a directory: anotherfunction() { [ same magic test ] || return 1 mkdir -p "$1" dostuff >> "$1/somefile" } If this were awk I would do the check like so: myvar ~ /^\// There *must* be a clean way to do this with the shell's string handling, but I'm having trouble coming up with it. (Mentioning a bash-specific solution would be fine but I'd like to know how to do this portably, also. POSIX string handling seems like it should be sufficient for this.)

/* ----------------- WANT TO RETURN1 ----------------- */  

machine: some value
server:	WANT TO RETURN1		
owner: some value	 	
notification: some value		
informatica: some value		
sap: some value	
group: This line contains a3 but can have space and characters


/* ----------------- WANT TO RETURN2 ----------------- */

server:	WANT TO RETURN2
machine: some value		
owner: some value	 	
notification: some value		
informatica: some value		
sap: some value	
group:  This line contains a1 but can have space and characters
unix: some value	 	
windows: some value		
aws: some value		
sap1: some value

/* ----------------- WANT TO RETURN3 ----------------- */  


owner: some value
machine: some value		
server:	WANT TO RETURN3	 	
notification: some value		
informatica: some value		
sap: some value	
group: This line contains a1 but can have space and characters


/* ----------------- WANT TO RETURN4 ----------------- */

server:	WANT TO RETURN4
machine: some value		
owner: some value	 	
notification: some value		
informatica: some value		
sap: some value	
group:  This line contains a2 but can have space and characters
unix: some value	 	
windows: some value		
aws: some value		
sap1: some value

Need to do with linux shell script if possible. I have some data in unix file as above. I have a file with multiple values for _STRING_TO_SEARCH_ like job.txt:

a1  
a2  
a3

Example - I want to run a for loop for each value of _STRING_TO_SEARCH_ and capture both _STRING_TO_SEARCH_ and server: value for that paragraph Desired output -

group: a1  
server: WANT TO RETURN2  
server: WANT TO RETURN3

group: a2  
server: WANT TO RETURN4  

group: a3  
server: WANT TO RETURN1

In each paragraph number of rows will vary and fields server: WANT TO RETURN and group:. This line contains a1 but can have space or characters can can occur on any row.

I'm using Debian 12 bookworm, gnu sed. I have this

-none
"Hello1"
"('41-Z', 5001, 'A6')" 
"'Hello2'"
"('42-Z', 5002, 'A7')"
'Hello3'
"('43-Z', 5003, 'A8')"

I want to modify only the lines with parenthesis entries, to appear like this:

-none
"Hello1"
'('41-Z', 5001, 'A6')'
"'Hello2'"
'('42-Z', 5002, 'A7')'
'Hello3'
'('43-Z', 5003, 'A8')'

How can I used sed to trade out the double quotes for single quotes of the lines in this example that have parenthesis, without interfering with the quotes of the other lines? This is a large text file that has hundreds, maybe thousands of these entries. I prefer sed, but I also tried looking for answers that use tr (truncate). Maybe someone has an awk answer.

The metadata of this file which resides on my HDD is written by CoW, therefore can I look for it just by using grep or strings, and the filename?

I have a string of text and spaces which looks like this: macOS windows arch-linux ubuntu_linux I want to append each item (with whitespace denoting a break between items) to a bash array. How do I do this?

I would like to generate a random string (e.g. passwords, user names, etc.). It should be possible to specify the needed length (e.g. 13 chars). What tools can I use? (For security and privacy reasons, it is preferable that strings are generated off-line, as opposed to online on a website.)

This question is similar to this one but it differs from it: Consider this array with string elements which may contain spaces: a@W:$ arr=("eins" "zwei" "eins plus zwei" "vier" "fünf") a@W:$ echo ${#arr[@]} # ok, 5 elements, as expected 5 a@W:$ echo ${arr} # the fourth one, indexing starts at 0 vier a@W:$ echo ${arr} # the third one, which contains two blancs eins plus zwei a@W:$ ar2=${arr[@]:0:3} # I only want the firs three of them a@W:$ echo ${ar2[@]} eins zwei eins plus zwei a@W:$ echo ${#ar2[@]} # but they are all glued together into one element 1 a@W:$ **What mus I do to prevent this gluing them all together?** The string containing spaces, "eins plus zwei" shall stay the third element.

I've to verify the length of variable read (my script limit to five the characters inserted), I think about something like this: #!/bin/bash read string check=${#string} echo $check if [ $check -ge 5 ]; then echo "error" ; exit else echo "done" fi is there a more "elegant" solution?

Update: Up to 2 "/" in the string. String structure is either: Character set name/LF Character set name/CRLF Character set name/CRLF/(unknown purpose, likely a number) Character set name Example: "UTF-8/CRLF" "UCS-2/CRLF/21" That is there may be only Character set name (unknown beforehand) without any "/" separator. Character set name may contain "-" and "_" (no need to separate here). Need to assign to: VAR1=Character set name VAR2=CRLF or LF part between 1st "/" and 2nd "/" (or empty string if there's no "/"). VAR3=Remainer after 2nd "/". Some kind of true/false (0/1) for VAR2 is OK also (it will be processed with if/else later in script). Tried cut -d/ -f, but cut -d/ -f 2 returns "Character set name" even **if there's no "/"**, so it doesn't work for me. For **Bash** script a **Faster** solution is preferred as it will be run many times. I do need to call a function as /bin/bash -c b/c its called in find -exec. Code (mostly based on Choroba's answer): #!/bin/bash shopt -s extglob function convert_single_text_file_to_utf8(){ CUR_FILE_ENCODING_WITH_CRLF=$1 echo "CUR_FILE_ENCODING_WITH_CRLF=${CUR_FILE_ENCODING_WITH_CRLF}" CUR_FILE_ENCODING_ONLY=${CUR_FILE_ENCODING_WITH_CRLF%%/*} # Remove everything starting from the last slash. LINE_FEED=${CUR_FILE_ENCODING_WITH_CRLF##$CUR_FILE_ENCODING_ONLY?(/)} # Remove the charset, followed by a slash if any. echo "CUR_FILE_ENCODING_ONLY=${CUR_FILE_ENCODING_ONLY} LINE_FEED=${LINE_FEED}" } export -f convert_single_text_file_to_utf8 for ENCODING in ASCII UTF-8/CRLF ISO-8859-2/LF EBCDIC-CA-FR; do echo "ENCODING=$ENCODING" export ENCODING /bin/bash -c 'shopt -s extglob; convert_single_text_file_to_utf8 "$ENCODING" ' done

I'm trying to check if the value inside a file is "0".

COUNT_EXECUTION=$(< /tmp/count)

if [ "$COUNT_EXECUTION" == "0" ]; then
  echo "Try restart service."
else
  echo "There is execution in progress."
fi

File content is just a 0, but the test always falls into the else

I want to use sed to search for line breaks that are not preceded by }. The regex for identifying theses cases is: [^}]$ . What I want to say: If the line ended without } then remove the new line. Any line should end with } before the newline. How to put that in sed to remove them? **EDIT:** Example: {'Date': 'Fri, 19 Apr 2019 07:23:14 GMT', 'Server': 'Apache', 'Vary': 'Qualys-Scan', 'Strict-Transport-Security': 'max-age=31536000;includeSubDomains;preload', 'Set-Cookie': 'ASP.NET_SessionId=ivoa5bhet0s2ygkylmimvkie; path=/; secure; HttpOnly;SameSite=strict, SC_ANALYTICS_GLOBAL_COOKIE=12f133ea; expires=Thu, 19-Apr-2029 07:23:14 GMT; path=/; secure; HttpOnly;SameSite=strict, SC_ANALYTICS_SESSION_COOKIE=336B5|1|ivoa5; path=/; secure; HttpOnly;SameSite=strict, incap_ses_885_270026=cDp/VlO1AHgshF9F6SZID==; path=/; Domain=.zurich.co.uk, ___utmvm=dlNaoEsuXSO; path=/; Max-Age=900, ___utmvay=nWJx01KvGT; path=/; Max-Age=900, ___utm=JZy XEtOwalQ: PtR; path=/; Max-Age=900', 'X-Content-Type-Options': 'nosniff', 'X-XSS-Protection': '1; mode=block', 'Cache-Control': 'private', 'Content-Type': 'text/html; charset=utf-8', 'Keep-Alive': 'timeout=5, max=10', 'Connection': 'Keep-Alive', 'X-Iinfo': '8-3925806-3807 NNNN CT(73 151 0) RT(155583 5) q(0 0 3 0) r(6 6) U5', 'X-CDN': 'Incapsula', 'Content-Encoding': 'gzip', 'Transfer-Encoding': 'chunked'} When I applied your script, it combined the lines. However, the new line starts with tab. How to also remove the spaces if the newline starts with spaces?

So I ran ips=$(arp | awk '{print $1}') to save all the IP addresses retrieved from the arp command into a variable, ips. echo of ips gives me Address 192.168.10.100 192.168.10.101 192.168.10.1. I am assuming that Address 192.168.10.100 192.168.10.101 192.168.10.1 is saved as string in the ips variable. What I want is a way to loop through the variable ips and maybe save the one in a variable, ip, do something with it, and move to next one.

I need to edit the string "NA" to "Na" only if it is in the 6th field of a file. I can currently achieve this with: awk '{gsub("NA","Na",$6)}1' $filename However I need the additional condition that this wont occur if the string "HEM" is in the same line. For example I would want the following line to stay the same: 7353 NA 5.4433 24.4404 -3.0784 NA 456 HEM Lastly, the above command removes the extra padding between fields. If there is a command that can accomplish this without changing the spacing between fields that would be awesome, but this feature is not necessary. I think this could be done with a while read through each file and printing each line, and only editing with an if statement, but I am trying to avoid something clunky like that. I feel like this one is a tall order to do in a simple fashion, but I would be super appreciative if any unix wizards know how. Thanks!

I have the following: COMMENT="A random comment" TEXT_JSON='{"person" : "Jim","comment" : "$COMMENT"}' echo "$TEXT_JSON" | jq . This prints { "person": "Jim", "comment": "$COMMENT" } which is not what I want. How can I interpolate the string here?

I have a json object that has an unknown number of variables, like this:

{ 
  "var1": 123, 
  "var2": 456, 
  "var3": 789 
}

How can I automatically convert it to form the following string?

'var1=123,var2=456,var3=789'

Note, I am looking for a solution that doesn't require installing jq.

I have a script that kicks off a new terminal window that I want to move to a specific position on the left terminal using xdotool. After kicking off the terminal I run xdotool search --class gnome-term and I use the returned Window ID in the xdotool windowsize and windowmove commands to size and position the new terminal window. xdotool windowsize $WIN_ID 1978 407 xdotool windowmove &WIN_ID -26 702 Since I have multiple terminals running I need to identify which WIN_ID is associated with the last terminal window just created. In the script I execute the below command before launching the new terminal to get a list of existing WIN_IDs. for i in xdotool search --class gnome-term; do id_list="$id_list $i"; done Sample content of $id_list: 65011713 65011722 65103242 65019818 65029314 65027106 After launcing the new terminal, to identify the new WIN_ID, I run this test. for WID in xdotool search --class gnome-term; do if [[ ! $WID =~ $id_list ]]; then echo "New Window ID = $WID"; fi; done When I run this command, instead of getting just one (the new) Window ID, I get all the Window IDs associated with the gnome-terminal class. Why is the below command not returning only the WID that isn't in id_list? if [[ ! $WID =~ $id_list ]]; then ... Script: ... ... # Generate a list of Window IDs for existing gnome-terminal windows for i in xdotool search --class gnome-term; do id_list="$id_list $i"; done # Kick off a new terminal window gnome-terminal # Get the Window ID of the new terminal window New_WID=for WID in xdotool search --class gnome-term; do if [[ ! $WID =~ $id_list ]]; then echo $WID"; fi; done ... ... Thanks for time and feedback! Tex

Let's say I have a string like this: title="2010-09-11 11:22:45Z" How can I grep the date itself and disregard the quotes/title/Z? The file can contain more strings like: randomstring title="2010-09-11 11:22:45Z" title="disregard me" So I only want to grep timestamps with a single grep command.

Sorry, this question is already answered for 'bash' here: Joining bash arguments into single string with spaces . in Fish, using

"'$*'"

leads to this error:

$* is not supported. In fish, please use $argv.

but I can't figure out how to join $argv elements to a single string with space between them. I also tried the

"${@}"

solution, which also doesn't work.

I set up a new, basic Linux server (CentOS in this case) just for testing purposes. In there, without any firewalls and all that I'm running a Python web application. Basically I type python run.py and have the application on foreground, while the application itself is run on some port like 8080, so in web browser I use I just type my_public_ip_addr:8080 and use it just fine. All this happens over SSH from my laptop. Now, I left my laptop open for a while, and when I came back, the shell was displaying something like this: 83.20.238.86 - - [13/Mar/2019 08:54:43] "GET / HTTP/1.1" 200 - 87.122.83.97 - - [13/Mar/2019 11:55:30] "GET / HTTP/1.1" 200 - 176.32.33.145 - - [13/Mar/2019 12:08:36] "GET / HTTP/1.1" 200 - 176.32.33.145 - - [13/Mar/2019 12:08:36] code 400, message Bad request syntax ('\x16\x03\x01\x00\xfc\x01\x00\x00\xf8\x03\x03(\xd3FM\xf5\x0eLo\x17\xa3|\x1f8\xca~#\x07\xc1\x1f&&\x14\x19\x11\x10:\x824\xd23nA\x00\x00\x8c\xc00\xc0,\xc02\xc0.\xc0/\xc0+\xc01\xc0-\x00\xa5\x00\xa3\x00\xa1\x00\x9f\x00\xa4\x00\xa2\x00\xa0\x00\x9e\xc0(\xc0$\xc0\x14\xc0') 176.32.33.145 - - [13/Mar/2019 12:08:36] "��(M�L⎺�≠8#�&&:�4┼A��▮�←�2�↓�/�→�1�↑���������(�$��" 4▮▮ ↑ 176↓32↓33↓145 ↑ ↑ [13/M▒⎼/2▮19 14:55:55] "GET / HTTP/1↓1" 2▮▮ ↑ 176↓32↓33↓145 ↑ ↑ [13/M▒⎼/2▮19 14:55:55] c⎺de 4▮▮← └e⎽⎽▒±e B▒d ⎼e─┤e⎽├ ⎽≤┼├▒│ ('\│16\│▮3\│▮1\│▮▮\│°c\│▮1\│▮▮\│▮▮\│°8\│▮3\│▮3\│92\│8e\│°7\│9e\│1▒\│▒2\│1e\│°8\│°bb^\│1b\│d1\│▒1\│1e\│d2\│d1^\│1e/└\│96_(\│beU\│▮4\│8d≥\│d7⎻\│°e\│▮▮\│▮▮\│8c\│c▮▮\│c▮←\│c▮2\│c▮↓\│c▮/\│c▮→\│c▮1\│c▮↑\│▮▮\│▒5\│▮▮\│▒3\│▮▮\│▒1\│▮▮\│9°\│▮▮\│▒4\│▮▮\│▒2\│▮▮\│▒▮\│▮▮\│9e\│c▮(\│c▮$\│c▮\│14\│c▮') 176↓32↓33↓145 ↑ ↑ [13/M▒⎼/2▮19 14:55:55] "���������b^[⎺⎼▒┼±e@ce┼├⎺⎽↑⎺⎼▒┼±e ⎺⎼▒┼±e_±c]$ ^C [⎺⎼▒┼±e@ce┼├⎺⎽↑⎺⎼▒┼±e ⎺⎼▒┼±e_±c]$ ┌⎺±⎺┤├ C⎺┼┼ec├☃⎺┼ ├⎺ 1▮4↓248↓36↓8 c┌⎺⎽ed↓ ▒d▒└@±⎽:·$ ▒d▒└@±⎽:·$ ▒d▒└@±⎽:·$ ▒d▒└@±⎽:·$ ec▒⎺ '▒e┌┌⎺ ⎽├▒c┐ ⎺┴e⎼°┌⎺┬' ▒e┌┌⎺ ⎽├▒c┐ ⎺┴e⎼°┌⎺┬ ▒d▒└@±⎽:·$ You can see 3 last "normal" GET requests to /, but then it begins. I know it can be fixed (link1 or link2 ) and these were some scanning bots, but my question is: **How does it work, that incoming request broke my terminal?**

I have a string that is the result of some operation I have no control over. When I print this variable using echo, I get: echo $myvar hello However, when I do if [ $myvar = "hello" ]; then echo they are equal else echo they are not equal fi I always get that they are not equal. I suspect this is because of a newline character. The string also behaves strangely. When I do: newVAR="this is my var twice: "$myvar$myvar echo $newVAR I get: hellois my var twice: hello How can I check if this is in fact due to a newline and, if so, remove it?