Questions tagged [unix]

Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs.

Excerpt from the Wikipedia page

Unix was originally written in assembly but has since been rewritten in C. It has been branched many times both commercially and open source. One popular variant is the BSD variant which originated from the University of California, Berkeley. It also gave rise to Linux.

Notable variants

  • Silicon Graphics - Irix
  • IBM - AIX
  • Sun Microsystems - Solaris
  • Hewlett Packard - HP-UX

Unix is officially trademarked as UNIX.

Unix on Wikipedia

1949 questions
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Create Unix Named Socket from the Command Line

Is there a command similar to mkfifo but for domain sockets?
benmmurphy
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Learning to compile things from source (on Unix/Linux/OSX)

While I install software from packages (MacPorts / apt-get) where-ever possible, I often find myself needing to compile packages from source. ./configure && make && sudo make install is usually enough, but sometimes it doesn't work - and when it…
Simon Willison
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How to find other end of unix socket connection?

I have a process (dbus-daemon) which has many open connection over UNIX sockets. One of these connections is fd #36: =$ ps uw -p 23284 USER PID %CPU %MEM VSZ RSS TTY STAT START TIME COMMAND depesz 23284 0.0 0.0 24680 1772 ? …
user13185
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3 answers

.nfsXXXX files appearing, what are those?

I have an application running (on RHEL5) that streams data onto an NFS share. Recently, I saw a lot of .nfsXXXX... (xxx being a hexadecimal number) appearing in its working directory, where the application writes hourly files and later moves them to…
nos
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How to determine the "age" of a linux system since installation?

I thought that I could easily check the timestamp of particular files. Then I realized that it wouldn't be so easy when I saw timestamps like 1991.
lisak
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Why is Linux reporting "free" memory strangely?

This is a canonical question about how Unix operating systems report memory usage. Similar Questions: Server refuses to use swap partition Memory Usage in LINUX I have production server that is running Debian 6.0.6 Squeeze #uname -a Linux…
user135199
44
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23 answers

Finding the Public IP address in a shell script

I can find my IP address using ifconfig or hostname -i command. But how do I find my Public IP? (I have a static public IP but I want to find it out using unix command)
shantanuo
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What is a good solution to encrypt some files in unix?

I am looking for a utility to encrypt certain directories in Linux. I am not looking for any full disk encryption services, but simply to encrypt a few directories for the purposes of storing files in the cloud. Once retrieving them, I should have…
Peter
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Why can't you fsck a mounted partition?

It's well-known that you should never fsck a mounted partition. I can understand how this could easily lead to corruption if the filesystem is written to by fsck (e.g., the -a option is used), but why can't read-only checks be run on mounted disks?
mike
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In tail -f, how do I filter out stuff that has certain keywords?

I want to tail -f my logs. However, I want to filter out everything that has the words: "ELB", "Pingdom", "Health"
Alex
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Faking the date for a specific shell session

I'm certainly trying to achieve something weird here, but I want to fake the date locally for a shell session on GNU/Linux. I need to black-box test how a program behaves at different dates, and modifying the system-wide date can have unwanted side…
nicoulaj
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Move files to another directory which are older than a date

I am looking for a solution to move files that are year older from today. My log partition is getting full, but I can not remove them. They are needed for a long long time. Anyway one solution I came up with is: find /sourcedirectory -mtime 365…
cr0c
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apt-get update/upgrade list without changing anything

I would like to view what packages are available for update/upgrade without actually changing any files becuase there are some packages I wouldn't like to update. Would it then be possible to apt-get update with exceptions.
John Magnolia
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What do these abbreviations stand for?

Some directories are easy to understand the meaning /usr /bin ... But for the next ones, I have no idea. /etc /opt opt for optional? etc for electronic t...... configuration (no idea for t) I would like to know what these abbreviations mean.
Luc M
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What is a zombie process and how do I kill it?

Virtual Shotguns?
jldugger
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