Leo Simon's questions

I use unison on a number of machines, all running ubuntu 20.04. For some baffling reason, one morning two of these machines starting opening a GUI whenever I did a file transfer. The other machine only generates text. The default.prf files on all machines are identical so that's not the source of the difference. I'd like to disable the GUI on the two machines that are running it. Couldn't find anything in the manual about how to do this. Could somebody advise please?

Thanks very much for any advise.

I'm running ubuntu 20.04, and am finding that on many but not all occasions, I cannot click on drop-down menus when I use google-chrome. This problem arises on all of my laptops, which are set up identically. A recent example of my problem is illustrated with the following website.

https://www1.onlinebanking.suntrust.com/UI/login#/enrollment

It prompts for Account type. The dropdown offers 5 options, including Mortgage. When I click on Mortgage nothing happens. I have to type the word in manually. I've tried the same URL using firefox and chromium-browser, and both work as expected, i.e., I click on Mortgage and the click triggers the word appearing in the dialog box. I've read of other people having problems of a similar nature, but the sites that I've seen all have special circumstances, and don't apply to me. Could anybody advise how to fix this please?

I'm embarrassed to ask this question, since there have been so many postings on the topic, but the discussions in them have been way above my paygrade, and I'm hoping somebody could give a really simple answer. I understand that /usr/bin/xterm can in fact support 256 colors (in spite of the fact that tput colors returns 8). But I'm been unable to generate more than 8 custom colors. For me the most understandable posting on this subject was by @alex, in this thread.

He gave this example:

fg_black="$(tput setaf 0)"
fg_red="$(tput setaf 1)"
fg_green="$(tput setaf 2)"
fg_yellow="$(tput setaf 3)"
fg_blue="$(tput setaf 4)"
fg_magenta="$(tput setaf 5)"
fg_cyan="$(tput setaf 6)"
fg_white="$(tput setaf 7)"
reset="$(tput sgr0)"

and then

echo -e "${fg_red}  Red  ${fg_green} Bull ${reset}"

did what you would expect Red in red and Bull in green.

Since xterm can support more than 8 colors I would have thought that, for example,

fg_purple="$(tput setaf 125)"

should give me a purple color and that

echo -e "${fg_purple} Purple ${fg_green} Bull ${reset}"

would return a purple bull. But I cannot for the life of me get any number beyond 7 to produce a color different from the xterm's default foreground color. Is there a simple way to accomplish this?

Thanks for any advice.

I have two machines both running 20.04. On one of them, I'm prompted for my user name, on the other the only prompt is for my password. I'm the only nonroot user in /etc/passwd. There was another subdirectory in /home---/home/leo, but there was never a separate user associated with that directory; it was a directory inherited from a previous installation.

So I deleted /home/simon and now /home contains just me i.e., /home/simon. But that didn't eliminate the username prompt. How would I convince ubuntu that there is only one user, and so go straight to a password prompt? Thanks!

When I use a zoom virtual background, my face looks like it belongs to a monster, and things like the couch in the room show through. In short it's hopeless. Is there some way to get a decent virtual background in ubuntu/zoom? I've read about deepbacksub but haven't seen how to download it.

And the article Background Substitution, No Green Screen Required seems to have figured out how to do it, but replicating the author's code is way beyond my ability. Is there software that I can simply apt to get a decent background?

I'm running the most recent version of zoom, dated 09/2020. Thanks for any suggestions.

I have a Google Drive directory called Ward.

I'm using gdrive, which is an otherwise wonderful tool, but I can't get it to upload to a directory. For example this works (my utility is called gdrive not the usual drive):

gdrive upload filename.pdf

This will send the file to the Google Drive home directory.

But trying the instructions from gdrive help upload,

gdrive upload -p Ward filename.pdf

throws an error file Ward not found.

I don't know if this is a hardware or software issue, but on my Dell XPS, running 18.04, when I type sudo fdisk -l I get all sorts of garbage that I don't want to see of the form

 Disk /dev/loop21: 140.9 MiB, 147722240 bytes, 288520 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes

I don't know what these /dev/loop devices are and certainly don't want to see any information about them. All I care about is my actual disks, and I'd like to see a summary that can fit onto one page.

I can eliminate the /dev/loop garbage by the call sudo fdisk -l /dev/[nv]* /dev/sd* but this command still produces way more information than I need.

This kind of output---which is more or less what 16.04 used to produce---would be ideal if there were some way of filtering out all of the extraneous garbage. That is, it just lists the available file systems and any partitions that are on them.

Disk /dev/nvme0n1: 953.9 GiB, 1024209543168 bytes, 2000409264 sectors

Device               Start        End   Sectors   Size Type
/dev/nvme0n1p1        2048    1023999   1021952   499M Windows recovery environment
/dev/nvme0n1p2     1024000    1228799    204800   100M EFI System
/dev/nvme0n1p3     1228800    1261567     32768    16M Microsoft reserved
/dev/nvme0n1p4     1261568  158547967 157286400    75G Microsoft basic data
/dev/nvme0n1p5   158547968  327999487 169451520  80.8G Linux filesystem
/dev/nvme0n1p6   327999488 1284618239 956618752 456.2G Linux filesystem
/dev/nvme0n1p7  1284618240 1835775999 551157760 262.8G Linux filesystem
/dev/nvme0n1p8  1835776000 1835778047      2048     1M BIOS boot
/dev/nvme0n1p9  1835778048 1967998975 132220928    63G Linux filesystem
/dev/nvme0n1p10 1967998976 2000408575  32409600  15.5G Linux swap



Disk /dev/sda: 28.9 GiB, 31004295168 bytes, 60555264 sectors
Disk /dev/sdb1: 30 GiB, 32212140032 bytes, 62914336 sectors

Perhaps there's an alternative to fdisk that's more customizable? Thanks for any advice!

I have a similar problem to the one reported in this thread., but I'm running Bionic Beaver

My machine is a Dell XPS 13. Wifi is working fine.

In settings -> Bluetooth, I'm told No bluetooth found, plug in a dongle

I've tried to turn the button on the top left corner of the screen from OFF to ON but am unable to do so

The solution below, suggested in in the thread cited above, doesn't do anything

rfkill unblock bluetooth
systemctl enable bluetooth.service
systemctl start bluetooth.service

Here's the output of the various commands requested in other posts:

lsusb; lsmod | grep bluetooth; dmesg | grep firmware
Bus 004 Device 003: ID 0bda:8153 Realtek Semiconductor Corp. 
Bus 004 Device 002: ID 0424:5537 Standard Microsystems Corp. 
Bus 004 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 003 Device 007: ID 046d:c00c Logitech, Inc. Optical Wheel Mouse
Bus 003 Device 005: ID 0bda:4014 Realtek Semiconductor Corp. 
Bus 003 Device 006: ID 413c:2010 Dell Computer Corp. Keyboard
Bus 003 Device 004: ID 413c:1003 Dell Computer Corp. Keyboard Hub
Bus 003 Device 003: ID 04a9:1792 Canon, Inc. 
Bus 003 Device 002: ID 0424:2137 Standard Microsystems Corp. 
Bus 003 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 003: ID 8087:0a2b Intel Corp. 
Bus 001 Device 002: ID 0bda:58f4 Realtek Semiconductor Corp. 
Bus 001 Device 004: ID 27c6:5385  
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
bluetooth             548864  28 btrtl,btintel,bnep,btbcm,btusb
ecdh_generic           24576  2 bluetooth
[    0.032829] Spectre V2 : Enabling Restricted Speculation for firmware calls
[    5.982838] [drm] Finished loading DMC firmware i915/kbl_dmc_ver1_01.bin (v1.1)
[    7.243912] iwlwifi 0000:02:00.0: loaded firmware version 34.0.1 op_mode iwlmvm

and

rfkill list all

returns

0: hci0: Bluetooth
        Soft blocked: no
        Hard blocked: no
1: phy0: Wireless LAN
        Soft blocked: no
        Hard blocked: no

I've used disper -l for many generations of ubuntu in order to determine which monitor I'm attached to, and whether an external monitor with either vga or hdmi is attached. Having now upgraded to 18.04, I find that this command is generating a segmentation fault. The problem seems to be around for a while, as reported in this bug report but nobody seems to be doing anything about it. Is there another program that has the same functionality? I've looked at xdpyinfo which has a lot of information, but not what I need, which is enough resolution information to distinguish between monitors, plus information about whether multiple monitors are attached, and by what connection.

Thanks!

I'm trying to disable chrome's default binding for Ctrl+H using shortkeys as discussed in this thread. For some reason, the fix proposed by @andreas_hacker isn't working for me. As per the comments in that thread, I'm posting this as a new question, so that Andreas can provide a step by step answer.

I'm running ubuntu 16.04 with windows 7 as a guest on virtualbox 5.40. I'd like to allow the windows guest to see a bluetooth microphone/headset which does not have a dongle. My understanding is that the way to pair in windows is Control Panel -> Hardware and Sound -> Add a Device. And windows is supposed to find any nearby bluetooth device that's in pairing mode.

But no device is recognized.

I've tried this both with bluetooth enabled and disabled on the host.

Any suggestions?

Thanks

As per request here's the output from lsusb

Bus 002 Device 011: ID 13fe:5500 Kingston Technology Company Inc. 
Bus 002 Device 001: ID 1d6b:0003 Linux Foundation 3.0 root hub
Bus 001 Device 048: ID 8087:0a2b Intel Corp. 
Bus 001 Device 009: ID 1bcf:2b91 Sunplus Innovation Technology Inc. 
Bus 001 Device 021: ID 0a5c:5800 Broadcom Corp. BCM5880 Secure Applications Processor
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

I had a dual boot setup on my Dell laptop with Ubuntu 16.04 and Windows 10. The tech replaced the motherboard and now I'm not able to boot. I am trying to restore GRUB - I installed a version of Ubuntu 16.04 on an USB stick, following the instructions on this site. Then I tried to boot from USB, but received this message:

Missing operating system
Selected boot device failed.

Can somebody tell me how to proceed?

xfinity wifi hijacks my system, so that even when I'm at home, I connect to xfinity rather than my much stronger home networks. I'd like to set a priority system so that good networks that I know (like my home networks) trump xfinity. It was hopeful that wifi-radar would accomplish this, but read on this site that it was no longer ubuntu friendly (and I can't get it to set a configuration file). Is there any way to accomplish such a priority system? Thanks for any advice

Under ubuntu 16.04 I get the following message

 Gtk-Message: GtkDialog mapped without a transient parent. This is discouraged

when I open zenity with the command

  zenity --text-info --filename=<filename>

This didn't happen under 14.04. I presume that the answer is related to this post but the post doesn't explain how to implement the proposed solution. Could somebody please explain which file I should add the suggested lines to?

You fix this warning by giving the GtkDialog a parent to be modal to. The relevant functions are gtk_window_set_transient_for() (which sets this window to always be on top of, or transient for, another one) and optionally gtk_window_set_modal() to make it a modal dialog. This is ultimately what the various GtkDialog constructors do.

I'm running Trusty-tahr using fvwm, so I don't automatically get access to the battery status icon that's available in the standard ubuntu desktop manager. I'd like to put the standard icon into my stalone tray, but I can't find a command-line command that will access the icon. I have the package indicator-power downloaded but there is no executable associated with this word.

Thanks for any advice.

Please note that because the information in this thread is all outdated, this question is not a duplicate.

I have the following command

find . -type f -print0 | xargs -0 chmod 644 

which would successfully change to 644 the permissions on all files in ., provided that the filenames contained no embedded spaces. However it doesn't work in general.

For example

touch "hullo world"
chmod 777 "hullo*"
find . -type f -print0 | xargs -0 chmod 644 

returns

/bin/chmod: cannot access `./hello': No such file or directory
/bin/chmod: cannot access `world': No such file or directory

Is there a way to modify the command so that it can deal with files with embedded spaces?

Thanks very much for any advice.

I'm trying to convert, from the command line, .png files of screenshots created by scrot to pdf files. I can successfully do this within shotwell, but I'd like to do it from the command line. For some reason, the command

convert file.png file.pdf

does a conversion, but it's not a literal one (and wont print properly)

For comparison purposes, I've posted on the web the output from convert

https://are.berkeley.edu/courses/ARE211/currentYear/convert.pdf

and the output from shotwell.

https://are.berkeley.edu/courses/ARE211/currentYear/shotwell.pdf

As you can see, the file convert.pdf is much much lower resolution, larger font, and most importantly, doesn't print properly using the standard lpr command.

Are the any off-the-shelf, easily installable, png to pdf conversion programs that would do a better job than convert? Or alternatively are there options to convert that I could use that would result in an exact conversion? There are a billion flags for convert, but I really don't know where to start.

Thanks for any help!

I'm trying to sync two ubuntu machines using unison. Unfortunately the documentation for this program is not terribly helpful. Also there doesn't seem to be an established forum. So I'm hoping somebody here has used it.

When I sync for the first time, using the most basic syntax

unison myHome ssh://root_to_remote//myHome

even though my profile file says

auto = true
times = true

I'm prompted about every single file in my filesystem, even for files that are of identical sizes, with the same modification times. Obviously, I'm doing something wrong, since unison is supposed to work with minimal user input.

I'd greatly appreciate any advice...

I have two computers connected to the same subnet.

The first (A) is running 14.04, the second (B) 12.04

I can ssh from the first to the second, but not from the second to the first.

Don't really know where to start to figure out why there's this difference.

However nmap is giving quite different results:

Computer (A), which is the one I can't get into:

PORT    STATE SERVICE
631/tcp open  ipp

Computer (B), which I can get into:

PORT    STATE SERVICE
22/tcp  open  ssh
53/tcp  open  domain
139/tcp open  netbios-ssn
445/tcp open  microsoft-ds
631/tcp open  ipp

Since the only port that's open on both is 631, I've tried ssh'ing from B to A specifying port 631, but that doesn't work either.

Could anybody please advise how to proceed?

I'm running ubuntu 12.04

I'm getting a huge number of "500 Internal Server Error" errors whenever I try to apt-get install/upgrade. aptitude yields exactly the same errors. I know there are supposed to be "zillions" of threads about this on the web but none of them seem to work for me. Most of them seem to be related to installing a specific package, but I get the errors whenever I use apt-get or aptitude

I know this is supposed to be a generic error, but there's nothing in the /var/log/apt folder that provides any information, or even acknowledges the error. (The only two files in there are term.log and history.log).

As some have recommended, I've modified my /etc/apt/sources.list file so that the top three lines are

deb http://us-west-1.ec2.archive.ubuntu.com/ubuntu/ precise main restricted universe multiverse
deb http://us-west-1.ec2.archive.ubuntu.com/ubuntu/ precise-updates main restricted universe multiverse
deb http://us-west-1.ec2.archive.ubuntu.com/ubuntu/ precise-security main restricted universe multiverse

But these are giving errors as well.

Can anybody please advise based on this information, or suggest how I can get a more informative error description?

Thanks for help in advance

Here are just a few of errors I get from apt-get upgrade

Err http://archive.canonical.com precise/partner amd64 Packages 500  Internal Server Error
Err http://archive.canonical.com precise/partner i386 Packages 500  Internal Server Error
Err http://archive.canonical.com precise/partner Sources 500  Internal Server Error
Err http://dl.google.com stable/main amd64 Packages 500  Internal Server Error
Err http://dl.google.com stable/main i386 Packages 500  Internal Server Error
Err http://extras.ubuntu.com precise/main amd64 Packages 500  Internal Server Error
Err http://extras.ubuntu.com precise/main i386 Packages 500  Internal Server Error
Err http://extras.ubuntu.com precise/main Sources 500  Internal Server Error
Err http://ppa.launchpad.net precise/main amd64 Packages 500  Internal Server Error
Err http://ppa.launchpad.net precise/main i386 Packages 500  Internal Server Error
Err http://ppa.launchpad.net precise/main Sources 500  Internal Server Error
Err http://security.ubuntu.com precise-security/main amd64 Packages 500  Internal Server Error
Err http://security.ubuntu.com precise-security/main i386 Packages 500  Internal Server Error
Err http://security.ubuntu.com precise-security/main Sources 500  Internal Server Error
Err http://security.ubuntu.com precise-security/multiverse amd64 Packages 500  Internal Server Error
Err http://security.ubuntu.com precise-security/multiverse i386 Packages 500  Internal Server Error
Err http://security.ubuntu.com precise-security/multiverse Sources 500  Internal Server Error
Err http://security.ubuntu.com precise-security/restricted amd64 Packages 500  Internal Server Error
Err http://security.ubuntu.com precise-security/restricted i386 Packages 500  Internal Server Error
Err http://security.ubuntu.com precise-security/restricted Sources 500  Internal Server Error
...
Err http://us-west-1.ec2.archive.ubuntu.com precise/main amd64 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise/main i386 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise/multiverse amd64 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise/multiverse i386 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise/restricted amd64 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise/restricted i386 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise-security/main amd64 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise-security/main i386 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise-security/multiverse amd64 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise-security/multiverse i386 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise-security/restricted amd64 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise-security/restricted i386 Packages 500  Internal Server Error
Err http://us-west-1.ec2.archive.ubuntu.com precise-security/universe amd64 Packages 500  Internal Server Error

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