String manipulation: extracting a part of a string, text replacement, formatting to a given width, etc.

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2
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1answer
26 views

How can I use sed to snip a line off of a string?

I'm writing a script to display the domain registrar info and I'm trying to snip off a few lines from what I already have I currently have it grabbing all the indented text from a whois. Now I'm ...
10
votes
3answers
669 views

How do you remove dot character from string without calling sed or awk again?

I have a file called hostlist.txt that contains text like this: host1.mydomain.com host2.mydomain.com anotherhost www.mydomain.com login.mydomain.com somehost host3.mydomain.com I have the ...
2
votes
4answers
62 views

String Manipulation Shell Script [duplicate]

I am working on a UPS Monitoring project using NUT Server. My objective is to make a shell script which sends one command and in response receives the status and other parameters from the UPS. for ...
0
votes
1answer
99 views

Find string in text file and execute a script depending of the result

I have a file (Data.txt) with something like this: A=1234597890 B=192.168.1.1 sometimes B goes first and sometimes only A or B. So, If I find: A, Print A content and execute A script B, ...
1
vote
2answers
45 views

How can I add a filter to my grep script to NOT include a string?

I'm working on a script that will separate the Registrar information from a domains whois. So far it's working enough but there are a few things that I want to remove in order for it to be a bit ...
1
vote
4answers
158 views

Extract substring with character instead of position

I recently got into nautilus scripts, and for the one I'm writing I'd need to extract a substrong from a filename. My problem is that I found tons of methods to extract a substring based on the ...
1
vote
3answers
47 views

How can I use string manipulation to detect and remove two different parts of a string?

I'm making a script that will remove the http:// or https:// from a URL. So far I've got it to remove the http://, but I can't seem to figure out how to modify it so that it will remove either that ...
0
votes
1answer
32 views

How to use the 'date' command to display week number of the year?

I want the UNIX date to output: So this is week 35 of 2016. Here, of course, 35 and 2016 are outputs of the date command. I have tried the following: date +%U This printed out the current week ...
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0answers
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How can I trim the whitespace immediately preceding and following a given character in python? [migrated]

I have a bunch of strings that look like this s = '| this is | my | made up string ' I'd like to write a function that removes all the whitespace immediately preceeding and ...
4
votes
5answers
4k views

Add leading characters in front of string using printf or echo

How can I add leading characters to fill a string to a certain length? Assume I want to add zeroes in front of a string, if said string is shorter than 20 characters: printf '%020s\n' "$line" ...
55
votes
11answers
116k views

Delete the last character of a string using string manipulation in shell script

I would like to delete the last character of a string, I tried this little script : #! /bin/sh t="lkj" t=${t:-2} echo $t but it prints "lkj", what I am doing wrong? Thank you in advance!
4
votes
2answers
3k views

Testing a string containing only spaces (tabs, or “ ”)? [duplicate]

My code below doesn't work: stringZ=" " if [[ "$stringZ" == ^[[:blank:]][[:blank:]]*$ ]];then echo string is blank else echo string is not blank fi Result: string is not blank # wrong ...
0
votes
1answer
53 views

grep with piping and showing multiple lines

I am trying to use grep to search a large text file, and return the paragraph containing a few key words. I also want to return the surrounding lines in the result. So, for example I have the ...
1
vote
4answers
46 views

Using cut to return the middle of a string

I have an xml string echoed to stdout along the lines of <xml:attribute>{41c33a-4893b-3627a-617a}</xml:attribute> I want to return the string {41c33a-4893b-3627a-617a} in this case. I ...
3
votes
4answers
146 views

Check if a shell variable has more than one line using built-ins?

I can do this by calling the external utility sed (for a known non-empty $myvar) like so: if [ "$(printf %s "$myvar" | sed -n '$=')" -eq 1 ]; then echo "Your variable has only one line, proceeding" ...
3
votes
5answers
121 views

Bash while loop read from colon-delimited list of paths using IFS

I am trying to write a bash function that behaves similarly to the where builtin in tcsh. In tcsh, where lists all the builtins, aliases, and the absolute paths to executables on the PATH with a given ...
0
votes
1answer
24 views

assign string components into variables [duplicate]

Looking for a smarter way to do something I'm doing already. I have a string: "firstbit.secondbit.thirdbit.fourthbit.fifthbit.sixthbit" The content between the periods changes, but the delimited ...
6
votes
5answers
951 views

Replace string after last dot in bash

I have the following pattern in a string (an IP address): 123.444.888.235 I want to replace the last number after the dot with 0, so it becomes: 123.444.888.0 How could I do it in bash or ...
0
votes
1answer
54 views

ZSH, concatenate passed in arguments into a single string

I would like to create a simple bash function to use for my convenience. Following the answer given at: Joining bash arguments into single string with spaces I've been able to mash up this small piece ...
2
votes
0answers
45 views

put string to commandline

I am making a bashfunction that show a menu binded to pgdown to browse through a a window which list my history (like 4dos/4nt etcetera). I have made so one line is always highlighted. $pos is ...
11
votes
7answers
35k views

How to get the first word of a string?

When I 'echo *' I get the following output: file1 file2 file3 ... What I want is to pick out the first word. How can I proceed?
4
votes
3answers
121 views

Remove substring from front and back of variable

I know that I can remove substrings from the front of a variable: X=foobarbaz echo ${X#foo} # barbaz ...and from the back of a variable: echo ${X%baz} # foobar How do I combine the ...
1
vote
4answers
126 views

How to break a long string into multiple lines in the prompt of read -p within the source code?

I am writing an installation script that will be run as /bin/sh. There is a line prompting for a file: read -p "goat can try change directory if cd fails to do so. Would you like to add this ...
1
vote
1answer
38 views

Bash: How to get a value from an array to create command from it

Is it possible to use bash to fetch a string from an array provided in the following syntax within a config file? | | Version | PackageManager | Webserver | Database | ...
1
vote
4answers
79 views

Bash part of string without using chars in quotes

So I want to get from a string like: q='"Something, variable", another part, third one' The part "Something, variable". I could get '"Something' using ${q%%,*}. But how could I let bash ignore ...
1
vote
2answers
26 views

How prepend appropriate amount of 0's to numbers contained in image names?

I've got a folder /User/me/Desktop/folder/images with files like key 1--name.jpg, key 10--name1.jpg, etc. The files are sorted incorrectly when fed to my site so I get an arrangement like key ...
17
votes
7answers
11k views

How to check if $PWD is a subdirectory of a given path

E.g. check if $PWD is a subdirectory of /home. In other words I'm searching for a bash string operation to check if one string starts with another.
0
votes
0answers
26 views

Problem matching strings in bash script

I`m making a script to rename files in a folder. The new name for the files is in a config file. I have to be sure that the file I want to rename corresponds to the current one in the config file. My ...
1
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3answers
49 views

Get directory name from file name

I want to make a directory name by extracting parts of a file name. Here are some examples: server.log.2016-03-20-14 → 20160320 server-2016-03-17-13-16-Restart.log → 20160317 I'm using HP-UX.
1
vote
3answers
43 views

How to get a substring based on index of another string

I need to extract the integer value from some log files. The integer value always appears after a substring return code. But it may or may not have additional stuff after this substring. Below are two ...
3
votes
1answer
63 views

Rewrite arguments before passing them to a command

I use rtorrent. When using magnetic-links, it creates a "meta"-file (.meta). This gets the form of a long hexadecimal-number (0-9, A-F). For example: 0123456789ABCDEF0123456.meta To "use" an ...
3
votes
3answers
41 views

Strings - Extract File Version Recursive

I have been using strings to extract and compare file versions between directories. I don't seem to be able to do this recursively. The method I have been using per file is: strings -e l ...
2
votes
5answers
87 views

how to cut fields of a directory name?

I have directory named 140905_M01771_0112_000000000-ABBYT. I want to get the third field i.e. 0112. I tried: cut -d _ -f 3 131230_M01771_0032_000000000-A7874 giving me error: cut: ...
3
votes
5answers
75 views

How to extract data from a file and construct a filename from one of the values

I'm trying to pull two values from a configuration file and write them to a new file. The hard part is that I want the name of the new file to be determined by one of the values in the input file. ...
1
vote
1answer
225 views

Find and delete lines containing multiple patterns in a file

I have a list of strings and want to find and delete lines containing these strings in a file. A short example of the list of strings is listed as below. File S 1Mo 32,33 2Mo 7,26 2Mo 7,27 2Mo 7,28 ...
3
votes
1answer
37 views

How to split a string on a control character?

I know how to split a string on a printable separator character; e.g. if the separator is ,: FOO='x,y,z' printf "%s\n" ${(s:,:)FOO} x y z But what if the separator is a control character, such as ...
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votes
2answers
26 views

How can I reformat MAC address and IP pairs, ensuring each byte of the MAC has a leading zero?

I've got a table like this: 10.6.6.12 0:50:56:9b:a6:2 10.6.6.13 fe:9:31:b6:71:1d I must have something like this: 10.6.6.12,00:50:56:9b:a6:02 10.6.6.13,fe:09:31:b6:71:1d A 0 is always added ...
3
votes
4answers
69 views

Bash converting path names for sed so they escape

I'm having a problem with a script. It is meant to change a value in a file called %DIR% so that it becomes a path name. The problem is the slashes in the directory name upset sed, so I get weird ...
1
vote
3answers
32 views

How can I parse JSON to test the string value of a nested key?

For example, here is my program's output (bspwm, if you wanted to know): { "id": 29360131, "splitType": "vertical", "splitRatio": 0.5, "birthRotation": 90, "vacant": true, "sticky": ...
0
votes
2answers
74 views

First line missing in concatenation of SSH output [closed]

I am trying to concatenate two strings in bash script but I am not able to get the expected result, USERNAME="ubuntu" MASTER="some IP" KEYFILE="/Path/to/keyfile.pem" STR1=`sudo ssh -q -t -o ...
0
votes
2answers
37 views

Retrieve string between two strings

I'm trying to extract a substring in the middle of two strings. I execute this grep command: echo "http://www.miweb.es/midoc-87-documento-texto_mf_4150310_1.txt" | grep -Po "(?<=midoc-).*(?=-)" ...
1
vote
1answer
40 views

Remove a part of a path from a variable content

In a Bash I have a variable: LOCAL_PATH="/this/is/a/path/" Then I have another variable, which content starts with LOCAL_PATH and it should be removed: LINE="/this/is/a/path/which/is/longer" The ...
1
vote
1answer
62 views

Combining strings command and grep: how to limit results to null-terminated strings

I have a feeling that it is strings which is thwarting my efforts here. The binary files I want to use strings on unfortunately yield several matches per file, even though it is a 100% rule that ...
4
votes
1answer
114 views

Append (alter) each array element via parameter expansion (i.e. without printf)?

Let the script below exemplify my quandary.. #!/bin/zsh STUFF=( moose-hoof ovary clydsedale ) echo ${MINE=$(printf "MY-%s " $STUFF)} echo ${MINE_EXP=${STUFF/^/MY-}} MY-moose-hoof MY-ovary ...
0
votes
1answer
39 views

Comparing a variable to upper and lower case letters

So I want to validate a response of a user in tcsh script and that's what I have so far set var1="temp" while($var1 != [yY] && $var1 != [Yy][Ee][Ss] && $var1 != [Nn] && ...
48
votes
6answers
85k views

How can I test if a variable is empty or contains only spaces?

The following bash syntax verifies if param isn't empty: [[ ! -z $param ]] For example: param="" [[ ! -z $param ]] && echo "I am not zero" No output and its fine. But when param ...
3
votes
7answers
449 views

Check if shell variable contains an absolute path

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 ...
0
votes
2answers
26 views

search the most latest's file name

I am writing a bash script to look for a file which's file name is most recently and file name like: ... Wed_Dec_30_16:47:41_PHT_2015.zip Wed_Dec_30_16:00:41_PHT_2015.zip ...
2
votes
2answers
85 views

How to append string with dash?

I am trying to append create a string that will be evaluated in the middle of a grep line. It is to find possible occurrences of different usernames within a certain file. However, I do not know how ...
1
vote
2answers
79 views

Use “find” from a specific relative directory [closed]

Suppose I'm in the following directory: /A-dir/B-dir/mydir/… some directories …/x-dir I want find to search from mydir, but mydir is not specifically known in advance; it is defined by the current ...