command "cat /etc/localtime" breaks output on tty-terminal
OS: Arch Linux 5.1.12-arch1-1-ARCH (tty1) Bash-Version: 5.0.7(1)-release localization: de_DE.UTF-8 UTF-8 keymap: de-latin1-nodeadkeys Description: The command "cat /etc/localtime" was called in a tty-terminal. After that some characters will be printed incorrectly (mostly "cyrillic" chars instead of the correct ones). The typed chars seems to be handled correctly (e.g. calling "exit") but the output is broken at this point. This behaviour is reproducible on my other PC with Debian Stable (Bash-Version in Debian: 4.4-5), so it seems to be a old bug. Changing to another tty or rebooting the OS will fix this behaviour until the command is called again. Kind regards, bitfreak
Re: command "cat /etc/localtime" breaks output on tty-terminal
On Sun, Jun 23, 2019, 5:31 AM bitfreak25 wrote: > OS: Arch Linux 5.1.12-arch1-1-ARCH (tty1) > Bash-Version: 5.0.7(1)-release > localization: de_DE.UTF-8 UTF-8 > keymap: de-latin1-nodeadkeys > > Description: > The command "cat /etc/localtime" was called in a tty-terminal. After that > some characters will be printed incorrectly (mostly "cyrillic" chars > instead of the correct ones). The typed chars seems to be handled correctly > (e.g. calling "exit") but the output is broken at this point. This > behaviour is reproducible on my other PC with Debian Stable (Bash-Version > in Debian: 4.4-5), so it seems to be a old bug. Changing to another tty or > rebooting the OS will fix this behaviour until the command is called again. > > Kind regards, > bitfreak > > /etc/localtime is symlinked to a file that contains time zone data. If you enter the command file -L /etc/localtime you'll see that that's the case. It contains data that's not meant to be displayed including control characters which cause the effect you observed. If you cat any so-called binary file such as this you are likely to see the same kind of thing happen. Entering the reset command in the affected terminal will correct the problem after it occurs.
Re: command "cat /etc/localtime" breaks output on tty-terminal
On Sun, 23 Jun 2019 06:04:29 -0500 Dennis Williamson wrote: > On Sun, Jun 23, 2019, 5:31 AM bitfreak25 wrote: > > > OS: Arch Linux 5.1.12-arch1-1-ARCH (tty1) > > Bash-Version: 5.0.7(1)-release > > localization: de_DE.UTF-8 UTF-8 > > keymap: de-latin1-nodeadkeys > > > > Description: > > The command "cat /etc/localtime" was called in a tty-terminal. After that > > some characters will be printed incorrectly (mostly "cyrillic" chars > > instead of the correct ones). The typed chars seems to be handled correctly > > (e.g. calling "exit") but the output is broken at this point. This > > behaviour is reproducible on my other PC with Debian Stable (Bash-Version > > in Debian: 4.4-5), so it seems to be a old bug. Changing to another tty or > > rebooting the OS will fix this behaviour until the command is called again. > > > > Kind regards, > > bitfreak > > > > > > > /etc/localtime is symlinked to a file that contains time zone data. If you > enter the command > > file -L /etc/localtime > > you'll see that that's the case. It contains data that's not meant to be > displayed including control characters which cause the effect you observed. > If you cat any so-called binary file such as this you are likely to see the > same kind of thing happen. Entering the > > reset > > command in the affected terminal will correct the problem after it occurs. I kind of thought that this could be the reason. It also happens with "cat /dev/urandom" which is stopped by [STRG] + [C]. It seems to be a very small bug thats only breaks the output with an unusual command and there are already 3 workarounds. But in my opinion it should be fixed some time as it isn't the correct behaviour like doing it with a gui-terminal e.g. xfce4-terminal. Kind regards, bitfreak
Re: command "cat /etc/localtime" breaks output on tty-terminal
On Sun, Jun 23, 2019, 7:18 AM bitfreak25 wrote: > On Sun, 23 Jun 2019 06:04:29 -0500 > Dennis Williamson wrote: > > > On Sun, Jun 23, 2019, 5:31 AM bitfreak25 wrote: > > > > > OS: Arch Linux 5.1.12-arch1-1-ARCH (tty1) > > > Bash-Version: 5.0.7(1)-release > > > localization: de_DE.UTF-8 UTF-8 > > > keymap: de-latin1-nodeadkeys > > > > > > Description: > > > The command "cat /etc/localtime" was called in a tty-terminal. After > that > > > some characters will be printed incorrectly (mostly "cyrillic" chars > > > instead of the correct ones). The typed chars seems to be handled > correctly > > > (e.g. calling "exit") but the output is broken at this point. This > > > behaviour is reproducible on my other PC with Debian Stable > (Bash-Version > > > in Debian: 4.4-5), so it seems to be a old bug. Changing to another > tty or > > > rebooting the OS will fix this behaviour until the command is called > again. > > > > > > Kind regards, > > > bitfreak > > > > > > > > > > > > /etc/localtime is symlinked to a file that contains time zone data. If > you > > enter the command > > > > file -L /etc/localtime > > > > you'll see that that's the case. It contains data that's not meant to be > > displayed including control characters which cause the effect you > observed. > > If you cat any so-called binary file such as this you are likely to see > the > > same kind of thing happen. Entering the > > > > reset > > > > command in the affected terminal will correct the problem after it > occurs. > > I kind of thought that this could be the reason. It also happens with > "cat /dev/urandom" which is stopped by [STRG] + [C]. > > It seems to be a very small bug thats only breaks the output with an > unusual command and there are already 3 workarounds. But in my opinion > it should be fixed some time as it isn't the correct behaviour like > doing it with a gui-terminal e.g. xfce4-terminal. > > Kind regards, > bitfreak > It's not a bug. It's expected behavior. If a useful sequence of control characters is output - useful things happen. If you take that away then lots of stuff doesn't work. Solution? Don't cat non-text files to the terminal. >
Re: command "cat /etc/localtime" breaks output on tty-terminal
On 6/23/19 8:18 AM, bitfreak25 wrote: > On Sun, 23 Jun 2019 06:04:29 -0500 > Dennis Williamson wrote: > >> On Sun, Jun 23, 2019, 5:31 AM bitfreak25 wrote: >> >>> OS: Arch Linux 5.1.12-arch1-1-ARCH (tty1) >>> Bash-Version: 5.0.7(1)-release >>> localization: de_DE.UTF-8 UTF-8 >>> keymap: de-latin1-nodeadkeys >>> >>> Description: >>> The command "cat /etc/localtime" was called in a tty-terminal. After that >>> some characters will be printed incorrectly (mostly "cyrillic" chars >>> instead of the correct ones). The typed chars seems to be handled correctly >>> (e.g. calling "exit") but the output is broken at this point. This >>> behaviour is reproducible on my other PC with Debian Stable (Bash-Version >>> in Debian: 4.4-5), so it seems to be a old bug. Changing to another tty or >>> rebooting the OS will fix this behaviour until the command is called again. >>> >>> Kind regards, >>> bitfreak >>> >>> >> >> >> /etc/localtime is symlinked to a file that contains time zone data. If you >> enter the command >> >> file -L /etc/localtime >> >> you'll see that that's the case. It contains data that's not meant to be >> displayed including control characters which cause the effect you observed. >> If you cat any so-called binary file such as this you are likely to see the >> same kind of thing happen. Entering the >> >> reset >> >> command in the affected terminal will correct the problem after it occurs. > > I kind of thought that this could be the reason. It also happens with > "cat /dev/urandom" which is stopped by [STRG] + [C]. > > It seems to be a very small bug thats only breaks the output with an > unusual command and there are already 3 workarounds. But in my opinion > it should be fixed some time as it isn't the correct behaviour like > doing it with a gui-terminal e.g. xfce4-terminal. All GUI terminals in my experience display the correct behavior. The correct behavior is to: - faithfully emit the output you requested - thereby emit control characters which the terminal cannot properly parse - break terminal output in some cases, depending on the control characters in question Some programs, unlike cat, try to protect you from this effect. See for example, $ curl file:///etc/localtime Warning: Binary output can mess up your terminal. Use "--output -" to tell Warning: curl to output it to your terminal anyway, or consider "--output Warning: " to save to a file. -- Eli Schwartz Arch Linux Bug Wrangler and Trusted User signature.asc Description: OpenPGP digital signature
