Activity for r~~
| Type | On... | Excerpt | Status | Date |
|---|---|---|---|---|
| Edit | Post #295535 | Initial revision | — | 7 months ago |
| Answer | — |
A: As root, how do I read another user's environment variables? Nobody likes it when their ‘how can I do this?’ questions are answered with ‘don’t do this’, but while an answer could be given that would probably work well enough most of the time for many use cases, the question itself is contradicted by how environment variables and `PATH` in particular are e... (more) |
— | 7 months ago |
| Comment | Post #295505 |
If your script won't function unless it is run with sudo, perhaps it should run sudo itself?
```
#!/usr/bin/env bash
echo "Current user: $EUID"
echo "Do things not requiring root now, like searching \$PATH"
sudo env what_we_found="42" "$BASH" <<'EXIT_SUDO'
echo "In sudo"
echo "Curren... (more) |
— | 7 months ago |
| Edit | Post #295454 | Initial revision | — | 7 months ago |
| Answer | — |
A: Replacing the shebang in a script Sed has more commands than just `s`! You can replace the first line of the input with a new value using the `c` command, without having to write any regular expressions. ``` sed "1c\\$env" "$file" ``` (more) |
— | 7 months ago |
| Edit | Post #295240 |
Post edited: |
— | 9 months ago |
| Edit | Post #295240 | Initial revision | — | 9 months ago |
| Answer | — |
A: How to enter a blank line in a terminal without executing the command > I've also tried using \ to escape the newline, but that also immediately executes, e.g. echo 'cat' \ just immediately prints > > cat > \ This shouldn't be happening. Ending a line with `\` in any sh-compatible shell is the standard way to represent a line continuation, per the ... (more) |
— | 9 months ago |
| Comment | Post #294901 |
This is a whole separate question about when parameter substitution happens, but you'll notice that the behavior changes when you replace your double quotes with singles. (more) |
— | 11 months ago |
| Comment | Post #294901 |
You can always get the exit status of the last command with `$?`. (more) |
— | 11 months ago |
| Edit | Post #294901 | Initial revision | — | 11 months ago |
| Answer | — |
A: trap ... ERR, how to get the signal code? `ERR` is not a signal, so there is no signal code to get. From `man bash`: > If a sigspec is ERR, the command arg is executed whenever a pipeline (which may consist of a single simple command), a list, or a compound command returns a non-zero exit status, subject to the following condition... (more) |
— | 11 months ago |
| Edit | Post #294547 | Initial revision | — | about 1 year ago |
| Answer | — |
A: Can I interrupt a crashing/frozen Ubuntu desktop? You might be looking for the Magic SysRq feature, which has many functions. One of the most useful is Alt+SysRq+f, which triggers the kernel's out-of-memory process killer. On Ubuntu, you may need to enable this feature using a sysctl configuration file. Either enable all Magic SysRq functions... (more) |
— | about 1 year ago |
| Edit | Post #294057 |
Post edited: |
— | over 1 year ago |
| Edit | Post #294057 | Initial revision | — | over 1 year ago |
| Answer | — |
A: Temporarily making \u escapes use a different encoding on the command line I don't think you can persuade Bash to use non-UTF-8 characters internally—I expect much of its code assumes that strings are ASCII-compatible. So `$'\u00FF'` will always translate, inside Bash, to the UTF-8 byte sequence `c3 bf`. If you want to take a UTF-8 byte sequence that Bash (or another... (more) |
— | over 1 year ago |
| Edit | Post #294056 | Initial revision | — | over 1 year ago |
| Answer | — |
A: greedy capture with sed The `b\+` part of the regex is already greedy. In sed, all repetitions are greedy. Your problem is that the initial `.` is also greedy, and so that's gobbling up both the `a` and as many `b`s as it can. For this example, you can change that part to `[^b]`: ``` $ sed -n 's/[^b]\(b\+\)./\1/p' <... (more) |
— | over 1 year ago |
| Edit | Post #293003 | Initial revision | — | almost 2 years ago |
| Answer | — |
A: how to use %F in a file URI in a .desktop file From the Desktop Entry Specification: > A command line may contain at most one %f, %u, %F or %U field code. Try storing %F in a local variable and reusing the variable. Also, take care: %F will in general expand to a list of files, which your current script will not adequately handle. U... (more) |
— | almost 2 years ago |
| Comment | Post #292980 |
Just to make sure, you do know that the output of the `h` command (and other commands with outputs) goes to the kernel log and not your current terminal, right? You need to run `dmesg` to see it. (more) |
— | almost 2 years ago |
| Edit | Post #291650 | Initial revision | — | over 2 years ago |
| Answer | — |
A: How do I send console output to the clipboard? On Wayland, the `wl-clipboard` utility `wl-copy` is the program you want: ``` echo hi | wl-copy ``` (more) |
— | over 2 years ago |
| Comment | Post #285187 |
Pick one, get corrected if necessary. (more) |
— | over 2 years ago |
| Edit | Post #291146 | Initial revision | — | over 2 years ago |
| Answer | — |
A: How do you generate arbitrary random numbers from /dev/random? You want `shuf`. ```sh shuf -n1 -i 534-876874 ``` (more) |
— | over 2 years ago |
| Edit | Post #291145 | Initial revision | — | over 2 years ago |
| Answer | — |
A: What is cat abuse/useless use of cat? Especially in a pedagogical context, the issue with something like `cat /dev/random | head -c 20` versus the more straightforward `head -c 20 /dev/random` is that it communicates that extra ceremony is necessary. It isn't. Using one program instead of two isn't about saving kilobytes of computer ... (more) |
— | over 2 years ago |
| Comment | Post #291137 |
`<file1 | grep cookies | wc` might work in your shell of choice but it doesn't work in Bash.
I look forward to your mocking rant about people who point out that other shells exist. (more) |
— | over 2 years ago |
| Comment | Post #290827 |
The answer says, ‘`sudo ls ~` [prints] the contents of your actual home directory [...] This is because [...] `sudo` [...] does not change your `$HOME`’. This is doubly false, as I explained—`sudo` can change `$HOME`, and the behavior of `sudo ls ~` doesn't depend on whether or not it does. (more) |
— | over 2 years ago |
| Edit | Post #290837 |
Post edited: |
— | over 2 years ago |
| Edit | Post #290837 | Initial revision | — | over 2 years ago |
| Answer | — |
A: How to use the gitignore file without git(1). You can fake out `git` as long as you have some empty Git repository available somewhere. ``` git --git-dir=path-to-empty-repo/.git \ ls-files --others --exclude-standard ``` (more) |
— | over 2 years ago |
| Comment | Post #290827 |
`sudo ls ~` will not tell you whether `sudo` sets `HOME`, because the `~` is expanded by the non-root user's shell. In many distributions, `sudo` *is* configured to set `HOME` by default. There are several configuration options that determine whether `sudo` modifies `HOME` or other environment va... (more) |
— | over 2 years ago |
| Edit | Post #290797 |
Post edited: cat isn't needed |
— | over 2 years ago |
| Suggested Edit | Post #290797 |
Suggested edit: cat isn't needed (more) |
helpful | over 2 years ago |
| Comment | Post #290716 |
Have you read what sudo does? If so, it's not clear what you want to know. If not, this is insufficient research for a question here. (more) |
— | over 2 years ago |
| Comment | Post #290201 |
On Debian Trixie, if you have the `console-setup-linux` package installed, [the files in that package](https://packages.debian.org/trixie/all/console-setup-linux/filelist) include terminal fonts of sizes up to 16x32.
And yes, the character grid is changed, not just the glyph sizes. A 16x32 fon... (more) |
— | almost 3 years ago |
| Edit | Post #290201 | Initial revision | — | almost 3 years ago |
| Answer | — |
A: How to change resolution of virtual terminal? This isn't exactly what you asked, but the letters-too-small problem could also be solved by using a larger console font. Here is a decent overview of how to change console fonts, though I don't know which of the `console-setup` and the `vconsole.conf` approaches is correct for your distribution. (more) |
— | almost 3 years ago |
| Edit | Post #290012 |
Post edited: |
— | almost 3 years ago |
| Edit | Post #290012 |
Post edited: |
— | almost 3 years ago |
| Edit | Post #290012 | Initial revision | — | almost 3 years ago |
| Answer | — |
A: Rename multiple files which have a variable suffix An easy one-liner in POSIX-compatible shells: ``` for f in -min.jpg-; do mv -- "$f" "${f%-}"; done ``` The only (mildly) tricky concept here is `${f%-}`, which expands to `$f` minus the shortest suffix matching the glob pattern `-`. (more) |
— | almost 3 years ago |
| Edit | Post #289874 |
Post edited: |
— | almost 3 years ago |
| Comment | Post #289874 |
That is a really good catch, thanks. (more) |
— | almost 3 years ago |
| Comment | Post #289874 |
Piping is a shell feature. If you want to use shell features, you have to be running in a shell. The `find` manual isn't responsible for pointing that out.
[It is specified](https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_13_03) that wildcards in shell scripts ... (more) |
— | almost 3 years ago |
| Comment | Post #289874 |
The `\! -empty` is there because if the shell expands a wildcard that doesn't match anything, the wildcard remains, and you don't want `.../empty_dir/*` in your output.
The `ls` is an unnecessary subprocess invocation. `sh` is already expanding the `*` before `ls` is invoked. (more) |
— | almost 3 years ago |
| Comment | Post #289875 |
Fair, post edited. (more) |
— | almost 3 years ago |