Frequently Asked Questions About Linux / UNIX » Easy

Ubuntu Linux: Install vim Text Editor

nixCraft — Sun, 19 May 2013 17:28:30 +0000

I recently switched from OS X to Ubuntu. When I run the 'vim file.c' command at terminal, I see an error message that read as follows:

The program 'vim' can be found in the following packages: * vim * vim-gnome
* vim-tiny * vim-athena * vim-gtk * vim-nox Try: apt-get install <selected package>

How do I fix this problem and why vim is not a default text editor on Ubuntu Linux? How can I install full-fledged vim text editor in Ubuntu Linux?

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Linux / Unix: View Overlapping Man Page With Same Names

nixCraft — Thu, 16 May 2013 19:06:02 +0000

I am a new Unix / Linux user. I am using whatis command to find man pages. But, I noticed that some man pages have a common names. For example, when I run whatis printf:
Outputs:
printf (1) - format and print data printf (1p) - write formatted output printf (3) - formatted output conversion printf (3p) - print formatted output printf [builtins] (1) - bash built-in commands, see bash(1)
How do I access overlapping man pages and what is the meaning of (1), (1p), (3), and so on?

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scp: Do not Overwrite Existing File On Linux or Unix System

nixCraft — Fri, 10 May 2013 20:03:49 +0000

I am a new Linux user. I use scp to upload files to net-storage provided CDN company. I do not want to overwrite the existing files. How can I prevent overwriting of files when using scp command under Linux, Mac OS X or Unix like operating systems?

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Ubuntu Linux: Install Wake On Lan Client For Server

nixCraft — Fri, 10 May 2013 10:14:05 +0000

How do I install wake on lan client under Ubuntu Linux desktop to wakeup Unix or Linux based servers?

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Linux / Unix: Find All Hidden Dot Directories and Delete

nixCraft — Sun, 05 May 2013 18:27:16 +0000

I need to clean up my backups stored on the nas server. I need to free up the disk space. How do I find out all hidden dot directories such as /nas01/backups/home/user/.gnome/, /nas01/backups/home/user/.gnome/ and so on and delete then in a single pass using Linux or Unix command line option? Please note that I do not want to delete nested hidden directories such as /nas01/backups/home/user/data/.xml, /nas01/backups/home/user/foo/bar/.level/.levle2/ and so on.

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Linux / Unix: Dig Command Find Out TTL (Time to Live) Value For DNS Records

nixCraft — Sun, 05 May 2013 05:53:32 +0000

I would like to see the Time-to-live (TTL) value for a 'AAAA' and A record for domains. How do I see Time-to-live (TTL) for a DNS record under Unix or Linux operating systems using command line options?

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Vi / Vim: Wipe and Undo All Changes Since Opening a File

nixCraft — Sun, 28 Apr 2013 20:11:25 +0000

I am a new vi / vim text editor user and I know how to quit without saving changes. What if I want to wipe out all of the edits I have made in a session and get back to the original file? How do I wipe all changes since opening a file?

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Apache 2: Reload HTTPD Configuration File Without Restarting Apache Config Changes

nixCraft — Sun, 28 Apr 2013 03:47:32 +0000

I made changes to the httpd.conf file. How do I reload the new config changes without restarting the Apache 2 web server under Debian / CentOS Linux operating systems?

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Linux / Unix: Shell Remove Empty Lines

nixCraft — Wed, 24 Apr 2013 20:46:54 +0000

I am a new Linux user. I have text files with lots of empty lines. How do I delete all empty lines under Linux or Unix operating systems?

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Bash: .* Considered Harmful To Match Dot Files. Why?

nixCraft — Wed, 24 Apr 2013 19:49:53 +0000

How do I match dot files under Unix / Linux using bash shell? Why .* considered as harmful when matching dot files under bash shell?

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HowTo: Unix rm All Files In a Directory

nixCraft — Wed, 24 Apr 2013 10:03:53 +0000

I am a new Unix user. How do I rm (remove) all files in a directory called personal-files under Unix like operating systems?

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Bash Function: Find Number Of Arguments Passed

nixCraft — Wed, 24 Apr 2013 10:02:59 +0000

How do I find out number of arguments passed to my bash function called foo() under Unix like operating systems?

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The Following Packages Were Automatically Installed And Are No Longer Required Warning

nixCraft — Wed, 24 Apr 2013 10:02:24 +0000

I have the following message whenever I use the apt-get command under Debian or Ubuntu Linux:

The following packages were automatically installed and are no longer required: libaccess-bridge-java libjs-mochikit python-cheetah libjs-excanvas libaccess-bridge-java-jni sabnzbdplus-theme-smpl tzdata-java ca-certificates-java Use 'apt-get autoremove' to remove them. 0 upgraded, 0 newly installed, 0 to remove and 4 not upgraded.

How do I fix this issue? Is it safe to remove all unwanted packages?

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HowTo: Check If a Directory Exists In a Shell Script

nixCraft — Sun, 14 Apr 2013 19:17:49 +0000

How do I check if a directory exists in a shell script under Linux or Unix like operating systems?

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VIM: Jump Back To Previous or Last Cursor Position

nixCraft — Sun, 14 Apr 2013 18:44:00 +0000

Writing shell scripts in vim I usually go search for functions or something. Copy lines and then go back to where I was and modify the code. However, I need to manually navigate way back to the previous / last position. How can I automatically go back to where I was when I started my search operation under vim?

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AWK: Remove All Blank Spaces From String / Field

nixCraft — Sun, 14 Apr 2013 18:14:54 +0000

I need to parse the following text file: # example.net config user = www30021 group = ftp30020 uid = 30021 gid = 30020 tmp_path = /netapp42/shared/www/images/host.example.com/tmp.bin tmp_perms = defaults,nodev,nosuid,noexec jail = on location = /jails/apache/h/host.example.com/ sftp = on ftps = off php-cgi = on perl-cgi = off I need to find out value for each field and remove any blank spaces / white spaces from the field. How do I solve this problem using awk under Linux or Unix like operating systems?

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Linux: Start / Stop / Restart Apparmor

nixCraft — Tue, 09 Apr 2013 18:43:40 +0000

AppArmor is a Linux Security Module (LSM) implementation of name-based mandatory access controls (MAC). How do I start / stop / restart AppArmor under Ubuntu Linux or OpenSuse / Suse Enterprise Linux server systems running on IBM hardware?

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SSH: WARNING: UNPROTECTED PRIVATE KEY FILE! Error and Solution

nixCraft — Tue, 09 Apr 2013 18:05:47 +0000

I'm setting up server on an Amazon EC2 compute instance powered by Suse Enterprise Linux server. I am using the following command to login into the my EC2 compute from OS X/Ubuntu desktop: ssh -i suse-ec2-server-jp.pem root@ec2-xx-yy-zzz-yyy.compute-1.amazonaws.com

I am getting the following error: @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ @ WARNING: UNPROTECTED PRIVATE KEY FILE! @ @@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@ Permissions 0440 for 'suse-ec2-server-jp.pem' are too open. It is recommended that your private key files are NOT accessible by others. This private key will be ignored. bad permissions: ignore key: suse-ec2-server-jp.pem Password: How do I fix this problem and login using ssh command?

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Linux / Unix Shell Script: Get The Current Directory

nixCraft — Tue, 09 Apr 2013 10:36:04 +0000

I am working on a shell script. I need to find out the current working directory. How do I get the current working directory under Bash or Ksh shell running on Linux or Unix like operating systems?

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FreeBSD: Delete User Account Command

nixCraft — Tue, 09 Apr 2013 09:21:22 +0000

How do I remove the tom user under FreeBSD operating system using command line options?

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