Questions tagged [coreutils]
GNU Core Utilities are the GNU project's implementation of the core command-line tools of a POSIX system, including tools like ls, cp, mv, rm, etc.
227
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What is the default behavior of GNU cp when copying from a symbolic link?
Can someone elaborate on this description in the official docs?
When copying from a symbolic link, cp normally follows the link only when not copying recursively or when --link (-l) is used.
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1
answer
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Can I force numfmt to always output a number scaled to Kilo instead of the auto-scale?
Can I make numfmt output the input number scaled to Kilo even when it is in another range, like in this sample Giga?
> LC_NUMERIC="en_US.UTF-8" numfmt --to=si --format=%.6f --suffix=Wh ...
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0
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date -d 'last month' yielding incorrect results? [duplicate]
I noticed an awkward (at least to me) behaviour of the date command:
jasio@zuza:~> date -d 'this month'
śro, 29 mar 2023, 15:51:42 CEST (1)
jasio@zuza:~> date -d 'last month' (2)
śro, 1 mar ...
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0
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What is the exact source of Architecture info in lscpu command
Tl;dr
I need to mock info about CPU architecture on the server for testing purpose. The only way that I can achieve it, is by changing info source about CPU architecture, that is used by lscpu command ...
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2
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225
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BusyBox's tar --exclude doesn't exclude
Extract a tar file with content dir1/dir2/file, using --exclude dir2 switch. The gnu tar excluded but busybox's tar doesn't.
Use --exclude dir1/dir2 works fine, but why? Is there a way to exclude any ...
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3
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2
answers
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What precisely does cp -b (--backup) actually do?
Before you hit me with the obvious, I know, the backup option makes a backup of a file.
But the thing is, the cp command in general backs up a file. One could argue a copy of a file is a backup.
So ...
2
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1
answer
346
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How do I use modern coreutils on Mac?
How do I get modern coreutils on mac?
I ran into this problem using csplit:
foo.txt:
foo
1
foo
2
foo
3
$: csplit foo '^foo$' '{*}'
# error
Double checking the manpage, man csplit, csplit on Mac is ...
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3
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517
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coreutils ls summary
Why is there no summary option in coreutils ls command, like MS-DOS/Windows has?
With summary option I mean:
count the files and dirs and sum up their sizes.
Update:
It should read: "Even DOS/...
- 153
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0
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14
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How to escape standard input when "cat f - g" [duplicate]
man cat shows the following example:
cat f - g
Output f's contents, then standard input, then g's
contents.
How do you escape the standard input and proceed to output the 2nd ...
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Does mv across filesystems flush the destination filesystem cache between copy and delete?
mv is implemented as a simple rename() whenever possible, falling back to copy-then-delete whenever renaming doesn't work. In practice (but not in theory), these two cases correspond to source and ...
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2
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Use Git Version of mv/rm etc When in Repository
Git has its own versions of commands such as mv and rm that we really ought to use when doing these operations inside repositories.
However, I'm sure I'm not the only person who often forgets to do ...
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2
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62
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Using cp -u but only if content is different
How to use cp -u to only copy if content is different, it fails when doing as below
$ cd /tmp/exper ; cp -v ~/Downloads/C/test.c . ; sudo chmod -R 777 .
/home/budi/Downloads/C/test.c -> 'test.c'
$ ...
user500425
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0
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157
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What dictates the order of group listing with id and groups command
I am trying to work out what order the groups are listed by id and groups command (coreutils v8.22)
I am using LDAP and have configured SSSD to read user and group information.
My ldap server always ...
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3
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110
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Seq but multiplying by the step instead of adding it
seq "prints a sequence of numbers to standard output", and, as far as I know, it can only increment the counter by adding.
For instance,
seq 0 3 10
0
3
6
9
tells seq to count from 0 to 10 ...
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1
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1
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Why do I need to specify `-o auto` for join's `-e` option to work?
With the following two simple files:
a.txt
1 a
2 b
5 c
b.txt
2 x
4 y
5 z
The following command does not behave like expected:
$ join -a 1 -a 2 -e 0 a.txt b.txt
1 a
2 b x
4 y
5 c z
I would expect ...
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9
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3
answers
3k
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Move files to directory based on extension (zsh, macOS)
I want to have a script to automatically move all files
into a directory structure that I have in place
(it looks like ~/jpg, ~/png, ~/mp3, ~/zip, and so on).
So far, this is almost doing exactly ...
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1
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3
answers
109
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Is there a unified stdout data format (for consistent/easy parsing) for core linux commands?
It seems that each core Linux command has a different stdout format. Also, these formats are not always easily/safely/consistently parsed by other scripts/apps.
Is there a wrapper or specification or ...
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1
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1
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128
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ln: create relative symlink to a relative symlink
I want to create a relative symlink pointing to a relative symlink, not to the relative symlink's target. It seems that when creating a relative symlink ln resolves TARGET instead of pointing to the ...
- 517
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1
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342
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How to intercept file descriptor of file opened with inotify or others on access?
I just finished an Operating Systems course at my University, and I want to start playing with systems level programs with Rust. One of things I'm looking for is how to intercept a file descriptor of ...
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3
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513
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Is there a Linux command that removes just the first character of every file?
Is there a Linux command that can remove the first character on the first line for every file in a folder, and then save it?
Many online resources cover doing this for every line instead of just the ...
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1
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1
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538
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Preserve permissions and ownership with install command
When running install (GNU Coreutils implementation), I'd like to know if it is possible to preserve ownership and permissions of the source files. I know that by default it installs as 755, and you ...
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1
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143
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If the `-p` flag not needed anymore in `mkdir` 9.0?
I can't find any reference of this change of behaviour
$ mkdir --version
mkdir (GNU coreutils) 9.0
Copyright (C) 2021 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <...
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-1
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1
answer
377
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How can I display directory file counts recursively with the ls command? [closed]
Under bash in Ubuntu, I want to ls -lah a directory and have it display file counts for directories recursively. That's to say I want it to count all files in the directories and their subdirectories....
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0
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272
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Are there any "richer" alternatives to cp and mv (like bat to cat and exa to ls)?
ls has exa. cat has bat. I don't know of a direct alternative to rm, but it also has rmtrash.
All of these can usually work as drop-in alias replacements, retaining usual function and options of their ...
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1
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205
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Help me understand a script that uses csplit and sed
I wanted a simple way to export notes from the reference manager, Zotero. I start by selecting multiple notes and dragging them into a blank text file.
I also want achieve "atomicity" of my ...
2
votes
1
answer
745
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How to treat a symbolic link as a file itself (instead of the one it points to)?
Out of curiosity i wanted to open a symlink as itself instead of the file it points to, just to see how it looks like. While there are ways to see what file it points to like using readlink and ways ...
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2
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ls: unparsable value for LS_COLORS environment variable zshell in fedora 33
I'm using zshell in fedora 33 OS.
I've the configuration in my ~/.zshrc file
Whenever I run ls command I get below error -
ls: unparsable value for LS_COLORS environment variable
How can I fix this ...
1
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0
answers
387
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Is jq internal sort slower than GNU sort?
While filtering through this json file I did a benchmark and found out utilizing jq's internal sort and unique method is actually 25% slower than sort --unique!
Command
Mean [ms]
Min [ms]
Max [ms]
...
2
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1
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763
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GNU cp: What's the difference between `--link` and `--reflink=always`?
What's the difference between --link and --reflink=always?
I use the following command as an mv substitute, and I am wondering if using --reflink is a better choice.
command gcp -r --link --archive --...
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4
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339
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what timedate value is always greater than any timedate?
What timedate value is always greater than any timedate?
In a script, I want to provide an argument to variable duration so that the loop will run forever until I kill the process:
# `duration` has a ...
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2
answers
251
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Making ls do a reasonable sort order, but not print Greek characters as "??"
Suppose I have the following files in a directory
_y a b c x z β
The following command lists them in the above order, as God intended:
perl -e '@files = <*>; print join(" ",sort @...
user39248
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68
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coreutils date does not return time zone when called from script
In terminal, the output of the lines
TZ="Australia/Broken_Hill" date -d '2021-4-26 09:29'
TZ="Australia/Broken_Hill" date -d '2021-4-26 09:29' +%Z
is
Mon Apr 26 09:29:00 AM ACST ...
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1
answer
2k
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What is %z useful for in GNU date?
I'm in the UK running these 2 commands (using gdate as I'm on a Mac with date (GNU coreutils) 8.32 installed):
# A UK winter date, timezone in UK at this time is GMT = UTC
$ gdate '--date=TZ="...
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0
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56
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Inconsistent output of cp -v command between machines
On two different machines I maintain, cp -v's output is different. On one box, both src and dest are quoted, on another box, the first quote around both src and dest is a backtick:
Box one (recent ...
- 3,700
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1
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395
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Interleaving two binary files by fixed-size blocks
We have paste(1) which can interleave files by lines. Out of
curiosity, I wonder if there's some binary equivalent. It should copy
the first N bytes from file A to stdout, then the first N bytes of ...
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0
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0
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39
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man -k . is not working in gnu/linux [duplicate]
I am using manjaro and when i try command man -k . or apropos . or man -k . -s 2 to see all man pages it's giving me error like
.: nothing appropriate.
is it man different because i gnu coreutils ? ...
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1
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Why does apropos and man -k omit or miss valid results?
For example, if I enter the following command:
$ man -k compare
The diff command is missing from the results, however the test command is not. I get the same results using apropos as expected.
$ ...
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2
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297
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Find filenames difference between two directories (ignoring filename extension)
I have a lot of files that I need to keep in sync as example:
./regular/*.txt
./compressed/*.txt.bz2
When files get uploaded to ./regular I want to make a script to periodically check and bzip2 ...
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1
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What is the difference between grep -r and find here?
I'm trying to recursively grep through files in a directory to find a certain string. The solution of my choice is:
$ find . -type f -exec grep "string to find" {} \+
... while using grep ...
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24
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3
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Why is cp's option not to overwrite files called --no-clobber?
cp is a massively popular Linux tool maintained by the coreutils team of the GNU foundation.
By default, files with the same name will be overwritten, if the user wants to change this behaviour they ...
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0
answers
45
views
ls output: group directory symlinks with directories [duplicate]
Using the --group-directories-first option I can group the ls output as follows:
[a-z directories] [a-z files and symlinks]
However, I would like symlinked directories to appear with the rest of the ...
- 909
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votes
1
answer
316
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GNU coreutils `sort` behave differently
I wanted to sort a list of data and I intended to sort it based on its first column which is an IP address.
192.168.1.100
192.168.1.101
192.168.1.110
192.168.1.119
192.168.1.20
192.168.1.30
192.168.1....
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How can I find out more about the history of GNU coreutils commands?
Can I somehow find out more about the history of the development process of the GNU coreutils commands? For example, have su and runuser (which provide kind of similar functions, yet were decided to ...
- 2,980
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1
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101
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Why did GNU's expand convert a tab to less than 8 columns?
Using expand, I don't understand how many spaces it converts tabs to. From info expand:
By default, expand converts all tabs to spaces. It preserves backspace
characters in the output; they ...
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12
votes
2
answers
1k
views
Explanation of tac --before
-b, --before
The separator is attached to the beginning of the record that it
precedes in the file.
And I can't understand the following output:
$ echo -e "Hello\nNew\nWorld\n!" > file
$ ...
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4
votes
1
answer
2k
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Why is mktemp -u considered "unsafe"?
I read the --help text for mktemp recently (the man page wasn't available) and came upon this:
-u, --dry-run do not create anything; merely print a name (unsafe)
Why is this "unsafe"? Is ...
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votes
5
answers
3k
views
How to run a command 1 out of N times in Bash
I want a way to run a command randomly, say 1 out of 10 times. Is there a builtin or GNU coreutil to do this, ideally something like:
chance 10 && do_stuff
where do_stuff is only executed 1 ...
- 319
1
vote
1
answer
536
views
What is the use of n option in cut command?
I'm learning about the cut command. In the man page of cut, they show the -n option like:
-n (ignored)
But I didn't understand the usage of the n option or when we would use it. Can anyone ...
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4
votes
1
answer
87
views
Why does ls sort results the way it does? [duplicate]
I'm just wondering why ls output is sorted the way it is:
$ mkdir SortTest<br>
$ cd SortTest<br>
$ for a in {1..34}; do touch filename_$a.txt; done
$ ls -l
-rw-r--r-- 1 user user 0 Jun 28 ...
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1
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1
answer
687
views
Translating Linux stat(1) command into BSD stat(1) command
Background
CLion's remote project feature currently doesn't support FreeBSD as a remote host OS, but I want to do some hacking and see if it works. By reading the log file, I think I have spotted (...
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