The Linux Questions Thread: a bunch of pitfalls, but technically it's possible

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > The Linux Questions Thread: a bunch of pitfalls, but technically it's possible

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Ninja Rope: Oct 22, 2005; Wee.

Did you install a VNC server on your windows machine? It's not there by default.

RDP is much more efficient and installed by default, but you'll get a new session every time you log out on the windows side. If you never log out you can keep reconnection to the same session.

# ? Nov 10, 2014 20:37

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# ? May 30, 2024 21:55

FISHMANPET: Mar 3, 2007; Sweet 'N Sour
Can't
Melt
Steel Beams

Yeah, in RDP there's a difference between logging out and disconnecting.

# ? Nov 10, 2014 20:46

nescience: Jan 24, 2011; h'okay

Ninja Rope posted:

Did you install a VNC server on your windows machine? It's not there by default.

RDP is much more efficient and installed by default, but you'll get a new session every time you log out on the windows side. If you never log out you can keep reconnection to the same session.

No the server is a linux machine. I installed xrdp so I can connect to it via rdp. But based on how the image is coming through I think its just VNC protocol. If im not getting a real RDP experience I might as well just use VNC, since I dont log out of the linux desktop on the server.

# ? Nov 11, 2014 08:48

Powered Descent: Jul 13, 2008; We haven't had that spirit here since 1969.

nescience posted:

No the server is a linux machine. I installed xrdp so I can connect to it via rdp. But based on how the image is coming through I think its just VNC protocol. If im not getting a real RDP experience I might as well just use VNC, since I dont log out of the linux desktop on the server.

Yeah, unfortunately xrdp doesn't act quite like you might expect session-wise for an RDP server for Linux. Straight VNC has its warts, but at least you can predict what those warts will be. If all your users are sysadmins, maybe ssh -X will do what you need.

# ? Nov 11, 2014 09:23

sector_corrector: Jan 18, 2012; by Nyc_Tattoo

I've been using Mint for a few months, and it's my first experience with Linux. I like it quite a bit. However, recently I've been having a problem with Spotify. It plays stuff alright from playlists, but the browse screen and search results have stopped displaying in the central pane of the application window. Does anyone have any ideas about how to fix this?

# ? Nov 11, 2014 19:20

Vulture Culture: Jul 14, 2003; I was never enjoying it. I only eat it for the nutrients.

Weird question: is it possible to get multiple hardware-accelerated X desktops on a single GPU, rendering to a graphics framebuffer but not necessarily being sent to an output display (think a use case like VNC, but with access to the GPU to do stuff like video scaling)? If not through X.org, what about Wayland or Mir?

# ? Nov 11, 2014 20:18

Suspicious Dish: Sep 24, 2011; 2020 is the year of linux on the desktop, bro; Fun Shoe

What do you want to do with that framebuffer if not send it to an output display?

# ? Nov 11, 2014 20:29

Vulture Culture: Jul 14, 2003; I was never enjoying it. I only eat it for the nutrients.

Suspicious Dish posted:

What do you want to do with that framebuffer if not send it to an output display?

I want to capture output from an application whose rendering path I may not directly control. Certain things it does will require GPU acceleration to perform well. (Not a good GPU, mind you, just something that can scale textures in hardware.)

Vulture Culture fucked around with this message at 21:42 on Nov 11, 2014

# ? Nov 11, 2014 21:27

covener: Jan 10, 2004; You know, for kids!

nescience posted:

No the server is a linux machine. I installed xrdp so I can connect to it via rdp. But based on how the image is coming through I think its just VNC protocol. If im not getting a real RDP experience I might as well just use VNC, since I dont log out of the linux desktop on the server.

maybe checkout freenx for marginally faster remote desktop on linux.

# ? Nov 13, 2014 03:21

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

Dumb newbie question:

I'm learning how to use vim. After saving using :wq the tutorial says I should see
"hello.txt" 4L, 64C written

I don't get that status message.

Is there an easy way to turn that on or should I ignore it until much later.

I'm thinking that I'd like to have it because it gives me a check against the tutorial to verify that I didn't miss a step.

# ? Nov 13, 2014 18:52

Powered Descent: Jul 13, 2008; We haven't had that spirit here since 1969.

Dr. Arbitrary posted:

Dumb newbie question:

I'm learning how to use vim. After saving using :wq the tutorial says I should see
"hello.txt" 4L, 64C written

I don't get that status message.

Is there an easy way to turn that on or should I ignore it until much later.

I'm thinking that I'd like to have it because it gives me a check against the tutorial to verify that I didn't miss a step.

That's what you'll see on the status line at the bottom if you save without exiting vi (that is, :w alone). Since you included the q, you've quit the program and so the status line isn't visible anymore.

# ? Nov 13, 2014 19:21

telcoM: Mar 21, 2009; Fallen Rib

Dr. Arbitrary posted:

I'm learning how to use vim. After saving using :wq the tutorial says I should see
"hello.txt" 4L, 64C written

I don't get that status message.

Is there an easy way to turn that on or should I ignore it until much later.

I'm thinking that I'd like to have it because it gives me a check against the tutorial to verify that I didn't miss a step.

The :wq is actually two commands put together. :w is "save the file, using its original name" and :q is "exit vim".

If you just want to see the message, the easiest way would be to enter those commands separately, and then you would see the message after the :w command.

The reason why you don't see the message with :wq is simple: as soon as the message is displayed, vim exits and the entire terminal display is overwritten by what was there before you started vim. This is because your terminal emulator has the "alternate screens" feature.

If you want, you could run a small experiment using plain old xterm (or its Unicode version, uxterm) instead of whatever fancy tabbed/transparent/desktop-environment-integrated terminal emulator you might be using:

1.) Start your (u)xterm. Just a very plain terminal window, right? But its ancient code holds some tricks...

2.) Move the mouse onto the xterm window, hold down the Control key and then hold down one of the mouse buttons. You should see a pop-up menu. There is a separate menu for each three mouse buttons, each full of ~~arcane runes~~ esoteric terminal options. Oh, and be careful, by the way: releasing the mouse button when the pointer is on a menu item will select that item.

3.) You'll want the "VT Options" menu, which is usually accessible by holding down Control and the middle mouse button. (If your mouse has two buttons and a scroll wheel, pushing the wheel down usually acts as the middle button.)

4.) There should be an option named "Enable Alternate Screen Switching". It probably has a check mark before it, meaning that alternate screen switching is enabled. To disable it, move the mouse to that line and release the mouse button. Now the option should be unselected.

5.) Now try the vim tutorial in the (u)xterm window. The :wq command should now behave as expected in the tutorial.

# ? Nov 13, 2014 19:59

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

telcoM posted:

The :wq is actually two commands put together. :w is "save the file, using its original name" and :q is "exit vim".

If you just want to see the message, the easiest way would be to enter those commands separately, and then you would see the message after the :w command.

The reason why you don't see the message with :wq is simple: as soon as the message is displayed, vim exits and the entire terminal display is overwritten by what was there before you started vim. This is because your terminal emulator has the "alternate screens" feature.

If you want, you could run a small experiment using plain old xterm (or its Unicode version, uxterm) instead of whatever fancy tabbed/transparent/desktop-environment-integrated terminal emulator you might be using:

1.) Start your (u)xterm. Just a very plain terminal window, right? But its ancient code holds some tricks...

2.) Move the mouse onto the xterm window, hold down the Control key and then hold down one of the mouse buttons. You should see a pop-up menu. There is a separate menu for each three mouse buttons, each full of ~~arcane runes~~ esoteric terminal options. Oh, and be careful, by the way: releasing the mouse button when the pointer is on a menu item will select that item.

3.) You'll want the "VT Options" menu, which is usually accessible by holding down Control and the middle mouse button. (If your mouse has two buttons and a scroll wheel, pushing the wheel down usually acts as the middle button.)

4.) There should be an option named "Enable Alternate Screen Switching". It probably has a check mark before it, meaning that alternate screen switching is enabled. To disable it, move the mouse to that line and release the mouse button. Now the option should be unselected.

5.) Now try the vim tutorial in the (u)xterm window. The :wq command should now behave as expected in the tutorial.

Thank you for the help! This is cool stuff. I have the day off of work tomorrow but I'm kind of excited to go in on Saturday to mess around with this some more.

# ? Nov 14, 2014 01:59

RFC2324: Jun 7, 2012; http 418

Dr. Arbitrary posted:

Thank you for the help! This is cool stuff. I have the day off of work tomorrow but I'm kind of excited to go in on Saturday to mess around with this some more.

You should set up a VM on your home machine to play with, it can be a hell of alot of fun poking around(I have found that a VM is perfect, sicne you can just keep a baseline you don't mess with to clone off when you inevitably break the system you are working on)

# ? Nov 14, 2014 02:58

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

I've got a new question:
I'm working through Learn Linux the Hard Way and I can't figure out a command:

https://nixsrv.com/llthw/ex5

quote:

Now, type man bash,/ (yes, just a slash), PS1, press <ENTER>.

I get that I'm supposed to be finding some reference to PS1 in the man page for bash. I read "man man" and it looks like it's a preprocessor string.

What is the correct syntax for this? I've tried a bunch of variations and they either fail or give me identical output to 'man bash'

# ? Nov 15, 2014 18:01

KozmoNaut: Apr 23, 2008; Happiness is a warm
Turbo Plasma Rifle

Dr. Arbitrary posted:

I've got a new question:
I'm working through Learn Linux the Hard Way and I can't figure out a command:

https://nixsrv.com/llthw/ex5

I get that I'm supposed to be finding some reference to PS1 in the man page for bash. I read "man man" and it looks like it's a preprocessor string.

What is the correct syntax for this? I've tried a bunch of variations and they either fail or give me identical output to 'man bash'

You're overthinking this, and the explanation sucks. / simply activates the search function in programs such as man, less, vim and so on, it's pretty much the standard.

So for instance, in the man page for bash, in order to search for "PS1", you type "/PS1" and press enter. To move to the next result, type 'n', to go back, type 'shift-n'.

To follow their formatting, it should be "man bash, <ENTER>, /PS1, <ENTER>".

I have to say, that guide seems overly simplified. It's basically just a laundry list of commands, but it doesn't really teach you why you're typing them, or what they're useful for. Unfortunately, I don't know of any better guides, I got thrown into the deep end ~12 years ago and learned the hard way :shobon:

KozmoNaut fucked around with this message at 18:51 on Nov 15, 2014

# ? Nov 15, 2014 18:48

Hollow Talk: Feb 2, 2014

I have a question about dracut:

I'm running openSUSE Factory on a 2014 MacBook Air, and since Linux has some trouble with the Intel backlight controls of the MBAs (namely that it can only be at 0% or 100% once the laptop has woken up again after having been put to sleep), I'm using mba6x_bl to control the backlight. This is working well enough and isn't a problem. However, whenever I create a new initrd with dracut (which is what sits behind mkinitrd), it subsequently also includes the mba6x_bl kernel module in the initrd, which results in the backlight not turning on properly, which I can only fix once I am logged in (external monitor and/or "typing blind" work).

Is there a way to generally blacklist this specific kernel module for dracut so that it doesn't end up in the initrd at all?

# ? Nov 15, 2014 18:56

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

KozmoNaut posted:

To follow their formatting, it should be "man bash, <ENTER>, /PS1, <ENTER>".

I have to say, that guide seems overly simplified. It's basically just a laundry list of commands, but it doesn't really teach you why you're typing them, or what they're useful for. Unfortunately, I don't know of any better guides, I got thrown into the deep end ~12 years ago and learned the hard way

Doh, that makes sense. I had every combination you could think of besides the correct one.

I'm finding this useful as a start. It's like trying to learn a language with just a dictionary written entirely in that language. The key is to get a small beachhead of things that you can almost understand. From there, you can start connecting the dots.

# ? Nov 15, 2014 19:01

evol262: Nov 30, 2010; #!/usr/bin/perl

Hollow Talk posted:

I have a question about dracut:

I'm running openSUSE Factory on a 2014 MacBook Air, and since Linux has some trouble with the Intel backlight controls of the MBAs (namely that it can only be at 0% or 100% once the laptop has woken up again after having been put to sleep), I'm using mba6x_bl to control the backlight. This is working well enough and isn't a problem. However, whenever I create a new initrd with dracut (which is what sits behind mkinitrd), it subsequently also includes the mba6x_bl kernel module in the initrd, which results in the backlight not turning on properly, which I can only fix once I am logged in (external monitor and/or "typing blind" work).

Is there a way to generally blacklist this specific kernel module for dracut so that it doesn't end up in the initrd at all?

dracut --omit-drivers mba6x_bl

Preferably by creating /etc/dracut.conf.d/99-mba.conf with
omit_drivers+=" mba6x_bl "

That way it'll do it every time new-kernel-pkg is run, or dracut is run (new-kernel-pkg ultimately calls dracut). But you can do it manually if you want.

Or add "rd.module.blacklist=mba6x_bl" to grub.

# ? Nov 15, 2014 19:29

Hollow Talk: Feb 2, 2014

evol262 posted:

dracut --omit-drivers mba6x_bl

Preferably by creating /etc/dracut.conf.d/99-mba.conf with
omit_drivers+=" mba6x_bl "

That way it'll do it every time new-kernel-pkg is run, or dracut is run (new-kernel-pkg ultimately calls dracut). But you can do it manually if you want.

Or add "rd.module.blacklist=mba6x_bl" to grub.

The second option works perfectly! Thanks a lot!

:toot:

# ? Nov 15, 2014 20:47

evol262: Nov 30, 2010; #!/usr/bin/perl

Hollow Talk posted:

The second option works perfectly! Thanks a lot!

Happy to help. Dracut isn't always fun, and I end up dealing with it a lot.

You can find out a lot by using rd.debug, rd.shell, and rd.break=... so you can play around in dracut itself.

Also, it's also shell, so recursively grepping /usr/lib/dracut is nice

# ? Nov 16, 2014 00:54

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

My goal is RHCSA, I'm currently working my way through LLTHW, (link in my earlier post.)

Are there any good resources or structured learning plans that can help me bridge the gap enough that I can pick up the Jang book for RHCSA and not be too far out of my depth?

I was thinking of getting the books for Comptia Linux+. I don't actually plan on taking that test of course, I can't imagine that it'd have any value compared to the RedHat cert.

In the meantime, I do have a server running WordPress and plenty of lab opportunities at work and home so I can probably dink around with this like it's a fulltime job.

# ? Nov 16, 2014 18:45

Blowjob Overtime: Apr 6, 2008; Steeeeriiiiiiiiike twooooooo!

telcoM posted:

Please run this command while the card & reader is plugged in and the Windows virtual machine is running:
code:
VBoxManage list usbhost
It should display a list of all your USB devices, with a block of information on each one. The first line on each block indicates the UUID (=a long string of numbers) VirtualBox uses to uniquely identify that device. Find the UUID of the USB card reader and make a note of it (copy & paste it somewhere, you're going to need it).

Then run:
code:
VBoxManage list vms
It will list the names and UUIDs of your virtual machines (I suppose you might only have the one virtual Windows so far).
Then, this command should allow the virtual Windows to access the card reader. Replace <name_of_your_virtual_machine> and <card_reader_UUID> with the appropriate name and UUID, and don't write the < and > characters around them (they are just to indicate things you must replace with the appropriate information).
code:
VBoxManage controlvm <name_of_your_virtual_machine> usbattach <card_reader_UUID>
This should be the equivalent of checking the card reader in the VirtualBox's USB device menu.
If this command runs without any error message, it's time to check the card reader program again.

If it works, please post the relevant information block from the "VBoxManage list usbhost" output; I (or perhaps someone else in this thread) could use it to suggest further settings to allow VirtualBox to automatically attach the card reader anytime it's plugged in.

I'm guessing that the virtual Windows is not yet permitted to access the USB device, and so the program behaves just as it does when the USB device is unplugged.

Reviving this old question about trying to get a proprietary USB storage card reader to work in a VM. For some background, the driver is installed in the VM, and the device is recognized, but when it gets to the point of actually trying to access the device to send data (in the case of this specific device, embroidery patterns for a sewing machine) the program included with the device freezes in the VM.

Per telcoM's instructions, I tried to attach the device through the terminal. This is the output:

code:

VBoxManage: error: USB device 'BROTHER USB-WRITER' with UUID {6fe31cc2-af14-48dd-8ba4-5cf6397e3750} is already captured by the virtual machine 'XP'
VBoxManage: error: Details: code NS_ERROR_INVALID_ARG (0x80070057), component HostUSBDevice, interface IHostUSBDevice, callee nsISupports
VBoxManage: error: Context: "AttachUSBDevice(usbId.raw())" at line 973 of file VBoxManageControlVM.cpp

So the VM sees the device, and Mint isn't trying to mount it outside the VM as a card reader based on the dmesg output referenced in the quoted post. With my inexperience, I'm not sure where to go from here. The device is hooked up and the VM recognized it.

The bizarre sticking point for me is that the device being attached is a card reader + memory card. Mint recognizes the reader without the card, and makes no acknowledgement when the card is plugged into the reader in that case. However, the program runs fine in the VM with the card reader attached, but freezes when the actual memory card is present. It almost seems like it would be easier if Mint would recognize the card itself, because as far as I can tell there is no acknowledgement of any change between the two states, one of which works fine, and one of which freezes the program.

# ? Nov 16, 2014 18:53

evol262: Nov 30, 2010; #!/usr/bin/perl

Dr. Arbitrary posted:

My goal is RHCSA, I'm currently working my way through LLTHW, (link in my earlier post.)

Are there any good resources or structured learning plans that can help me bridge the gap enough that I can pick up the Jang book for RHCSA and not be too far out of my depth?

I was thinking of getting the books for Comptia Linux+. I don't actually plan on taking that test of course, I can't imagine that it'd have any value compared to the RedHat cert.

In the meantime, I do have a server running WordPress and plenty of lab opportunities at work and home so I can probably dink around with this like it's a fulltime job.

The RHCSA track for RHEL7 is somewhat different then 6. I don't know that Jang's updated. But the study guides can definitely help bridge the gap. I may be able to help you with that since you're local and all, and it sounds like we'll be meeting.

# ? Nov 17, 2014 00:08

Gucci Loafers: May 20, 2006; Ask yourself, do you really want to talk to pair of really nice gaudy shoes?

Jang posted earlier in a different forum that he's working on a new version for rhel7. It should be out sometime in January.

# ? Nov 17, 2014 04:59

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

I already own the Jang 6 book so even if it's not exactly what I need for RHEL7 it should still be information that's important for me to know. If I can get it all down by January then R7 should be a piece of cake.

# ? Nov 17, 2014 05:57

Gucci Loafers: May 20, 2006; Ask yourself, do you really want to talk to pair of really nice gaudy shoes?

Same here, thought I've heard RHEL6 to 7 is big jump? Maybe someone else could comment more?

Are you follow this? https://nixsrv.com/llthw

# ? Nov 17, 2014 06:33

evol262: Nov 30, 2010; #!/usr/bin/perl

6->7 is jumping from Fedora 11/12 to 19/20. firewalld, systemd, logind, and a lot of other base tools were added or changed. Plus it's all lab now. With no real focus on the GUI tooling at all. I'm not gonna say that 6 is totally useless, but that 7 is designed to be a relevant, real-world track that 6 never quite lived up to.

A lot of stuff (automounter, PAM bits, kerberos, shell utilities, kickstarts, dracut [mostly -- some dracut bits changed which are principally used in pxe kickstarts]) is pretty much the same. A lot isn't, though. Reading a recent Fedora admin/deployment/security guide or the rhel7 deployment guide may not be a bad idea

# ? Nov 17, 2014 06:57

revmoo: May 25, 2006; #basta

I have a server with a bunch of practically freeloading clients I can't seem to get rid of. I recently got hit with the drupal hack and a couple sites got trashed by some drunk Romanians.

I'm setting up a fresh server. What's the quickest/easiest way to get virtualization up and running on Debian or Ubuntu? I need something that lets me make machine snapshots and do stuff like push ip addresses around. I'd rather not pay but if VMware is the ticket then I can be convinced. I want to keep my entire customer layer virtualized so that I can move it between physical machines with only an ip reconfig.

# ? Nov 17, 2014 14:21

evol262: Nov 30, 2010; #!/usr/bin/perl

revmoo posted:

I have a server with a bunch of practically freeloading clients I can't seem to get rid of. I recently got hit with the drupal hack and a couple sites got trashed by some drunk Romanians.

I'm setting up a fresh server. What's the quickest/easiest way to get virtualization up and running on Debian or Ubuntu? I need something that lets me make machine snapshots and do stuff like push ip addresses around. I'd rather not pay but if VMware is the ticket then I can be convinced. I want to keep my entire customer layer virtualized so that I can move it between physical machines with only an ip reconfig.

If you want a GUI, apt-get install virt-manager. If not, follow any one of the hundreds of KVM guides (KVM works basically out of the box anyway).

Recent versions of libvirt can live migrate without shared storage. I have no idea what ubuntu/Debian ships. You may want shared storage anyway. Anything you can mount works (fc, iscsi, nfs, ceph, drbd, gluster).

Or copy disks and configs around by hand

I'd strongly suggest ovirt or xenserver or xcp or another virtualization platform for anything other people may have to touch.

# ? Nov 17, 2014 14:53

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

Is there an easy way to search for special characters when using less? I'm trying to find details on things like $, /, or ? in the man pages but I guess the search bar is treating those as special search operations.

# ? Nov 17, 2014 19:06

FISHMANPET: Mar 3, 2007; Sweet 'N Sour
Can't
Melt
Steel Beams

Try putting a backslash in front of them. So for example, after opening a file in less, type "/\$" and hit enter and that should open the search dialog and search for $.

# ? Nov 17, 2014 19:13

Dr. Arbitrary: Mar 15, 2006; Bleak Gremlin

FISHMANPET posted:

Try putting a backslash in front of them. So for example, after opening a file in less, type "/\$" and hit enter and that should open the search dialog and search for $.

Aha! I guess I should have thought to search man bash for "escape character"

Thanks for being patient with my questions, I'm really trying to get what I need in order to help myself, hence the focus on learning how to search man pages, finding good online resources, etc.

# ? Nov 17, 2014 19:54

Vulture Culture: Jul 14, 2003; I was never enjoying it. I only eat it for the nutrients.

Dr. Arbitrary posted:

Aha! I guess I should have thought to search man bash for "escape character"

Thanks for being patient with my questions, I'm really trying to get what I need in order to help myself, hence the focus on learning how to search man pages, finding good online resources, etc.

What you're doing is awesome! Anyone who makes you feel bad for asking newbie questions is a bad person and should feel bad (and then be ostracized from any community they identify with).

# ? Nov 17, 2014 20:47

FISHMANPET: Mar 3, 2007; Sweet 'N Sour
Can't
Melt
Steel Beams

Man, Unix is hard, and it's even harder when stupid gate keepers try and keep people out, which the "community" seems to be full of.

# ? Nov 17, 2014 20:48

pseudorandom name: May 6, 2007

Dr. Arbitrary posted:

Aha! I guess I should have thought to search man bash for "escape character"

Thanks for being patient with my questions, I'm really trying to get what I need in order to help myself, hence the focus on learning how to search man pages, finding good online resources, etc.

In this particular case, you'd want to look at the less man page where it explains the /pattern command and then follow up with man 7 regex to read about regular expressions.

# ? Nov 17, 2014 20:53

evol262: Nov 30, 2010; #!/usr/bin/perl

pseudorandom name posted:

In this particular case, you'd want to look at the less man page where it explains the /pattern command and then follow up with man 7 regex to read about regular expressions.

It's worth noting that in case you already know regular expressions, GNU and POSIX regexps are somewhat more limited, and the manpage is worth reading either way -- to learn what you can do, or to learn what you can't do.

# ? Nov 17, 2014 20:57

ToxicFrog: Apr 26, 2008

evol262 posted:

It's worth noting that in case you already know regular expressions, GNU and POSIX regexps are somewhat more limited, and the manpage is worth reading either way -- to learn what you can do, or to learn what you can't do.

GNU and POSIX EREs are strictly more powerful than formal regular expressions, though? :confused:

# ? Nov 17, 2014 21:04

evol262: Nov 30, 2010; #!/usr/bin/perl

ToxicFrog posted:

GNU and POSIX EREs are strictly more powerful than formal regular expressions, though?

Yes but no. Most of the time, I tend to refer to PCREs (and analogues) as "regular expressions". EREs are nowhere near as powerful as the regexps in the vast majority of programming languages/libraries, which can do things like negative lookaheads, named grouping, maybe unicode etc. Some are relatively bad (go), some are exceptionally good (perl), but all are basically more powerful than EREs.

Who uses "formal" (incredibly limited) regular expressions?

# ? Nov 17, 2014 21:42

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# ? May 30, 2024 21:55

Vulture Culture: Jul 14, 2003; I was never enjoying it. I only eat it for the nutrients.

ToxicFrog posted:

GNU and POSIX EREs are strictly more powerful than formal regular expressions, though?

It isn't the 1970s. Anyone writing actual software outside of a PDP-8 is referring to Perl-compatible regular expressions unless they've specified otherwise.

# ? Nov 17, 2014 21:43

The Something Awful Forums > Discussion > Serious Hardware/Software Crap > The Linux Questions Thread: a bunch of pitfalls, but technically it's possible

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