Top new questions this week:

Why isn't Linux embraced as the official GNU kernel?

While I knew for quite some time the existence of Hurd, and its mission as the official GNU Operating System kernel, I was wondering how come Linux is not embraced as the official GNU kernel over the …

/ linux-kernel / gnu / hurd

asked by NlightNFotis 37 votes answered by goldilocks 43 votes

How safe is it to cat an arbitrary file?

Sometimes when I cat a binary file by mistake, my terminal gets garbled up. Nothing a quick reset can't fix, but couldn't an attacker theoretically create a file that, when displayed on a terminal, …

/ terminal / cat / special-characters

asked by Gunchars 24 votes answered by Anthon 12 votes

In what situations would a user not let the shell record his command into history?

I find if add this line in .bashrc, bash won't record any commands which have whitespace before them into history: export HISTCONTROL=ingorespace. But I do not understand under what situations it …

/ bash / shell / command-history

asked by acgtyrant 13 votes answered by Ulrich Dangel 25 votes

SSH ignores characters after correct password string?

Remote machine 10.10.10.1 has password "asdFGH12" for user named "user". I'm able to log in even if I type in password "asdFGH12dasdkjlkjasdus" or any other characters after the "asdFGH12" string. $ …

/ password / authentication / sshd

asked by Martin 13 votes answered by Chris Down 21 votes

How to cycle through reverse-i-search in BASH?

In the terminal, I can type CRTL+R to search for a matching command previously typed in BASH. E.g., if I type CTRL+R then grep is lists my last grep command, and I can hit enter to use it. This only …

/ bash

asked by Village 11 votes answered by Sukminder 16 votes

difference between function foo() {} and foo() {}

I can define bash functions using or omitting the function keyword. Is there any difference? #!/bin/bash function foo() { echo "foo" } bar() { echo "bar" } foo bar Both calls to functions …

/ bash / shell / function / posix

asked by Carlos Campderrós 9 votes answered by schaiba 7 votes

After researching, still confused about monitoring RAM usage

I went through this article, which explains various methods for checking your RAM usage. However, I can't reconcile the different methods and don't know which one is correct. When I first login, I'm …

/ linux / memory

asked by Jonah 9 votes answered by Rahul Patil 4 votes

Greatest hits from previous weeks:

Repeat a Unix command every x seconds forever

There's a builtin Unix command repeat whose first argument is the number of times to repeat a command, where the command (with any arguments) is specified by the remaining arguments to repeat. For …

/ command-line / scripting / utilities

asked by dreeves 83 votes answered by Gregor Brandt 128 votes

ssh-add complains: Could not open a connection to your authentication agent

I've been trying to get ssh-add working on a RaspberryPi running Raspbian. I can start ssh-agent, when I do it gives the following output into the terminal: …

/ command-line / ssh / ssh-agent

asked by Daniel Groves 10 votes answered by Stephane Chazelas 15 votes

Can you answer these?

Using x509 PKI with PGP

I'm building x509 PKI. And I want to apply CA's concept to my own private apt-get repository. I just found that apt-get repository (reprepro) use PGP certificate and some textbook said they can't use …

/ pgp

asked by vernomcrp 1 vote

Flashing rootfs on Embedded Linux with Limited RAM

I'm fairly new to the embedded world, so forgive me if this seems obvious. I'm working on a board based off of the AT91SAM9260. I have 256MB of flash and 64MB of RAM. The current setup flashes two …

/ partition / embedded / root-filesystem

asked by trycatch 2 votes

Gnome Terminal---hide the tilde files produced by Emacs

Editing text file using Emacs will make Emacs make a companion file for its own purpose. For example, after first editing a file called test.c, Emacs will leave a file called test.c~ in the same …

/ emacs / gnome-terminal

asked by xiaohan2012 2 votes