Questions about the command line and other Unix-like aspects of Mac OS X, including the Mach/BSD-based kernel and FreeBSD-based userland. You may want to consider using Ask Different instead.

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11
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2answers
525 views

awk memory leak?

Base on this I'm running the command < /dev/urandom hexdump -v -e '/1 "%u\n"' | awk '{ split("0,2,4,5,7,9,11,12",a,","); for (i = 0; i < 1; i+= 0.0001) printf("%08X\n", ...
11
votes
1answer
4k views

Setting vim filetype with modeline not working as expected

As per the accepted answer to this question, I'm attempting to use modelines in vim to force filetype detection in some files. For example, at the top of a file named gitconfig (note there is no ...
11
votes
3answers
11k views

Mac OS X: dircolors not found?

I just switched to a Macbook Air. I installed zsh using homebrew, but when I use some of the code that I (originally had) in my .zshrc, I get an error saying that .dircolors was not found. Below is ...
11
votes
2answers
19k views

Global bash_profile

I realize there are /etc/profile and /etc/bashrc files for setting global environment variables and maybe I'm just misunderstanding their purposes, but... Is there a global bash_profile file? I'm ...
11
votes
6answers
2k views

Disable Keyboard & Mouse Temporarily

I would like to know how one can disable the keyboard & mouse temporarily in OS X.
10
votes
2answers
1k views

Is it OK to use “.” to run files instead of source - in .bashrc in Ubuntu and OS X?

OK, so source runs the script in the current shell and . separately, as detailed in running script with ". " and with "source " for example, but, specifically, in my .bashrc file, ...
10
votes
1answer
14k views

+ or @ mark after running 'ls -al'

In Mac OS X, run 'ls -al' gives me something like this. drwxrwxrwx+ 4 smcho staff 136 May 5 09:18 Public drwxr-xr-x+ 6 smcho staff 204 Feb 1 2010 Sites drwxrwxrwx 9 smcho staff ...
10
votes
1answer
5k views

Bash history with timestamps

I would like to keep timestamps on the commands logged in my Bash $HISTFILE, is it possible? I did not manage to set it up using man bash as an information source. My other options are as follows: ...
9
votes
5answers
17k views

Simple sed replacement of tabs mysteriously failing

This ought to be really simple, but for some reason it is not working: sed -i.bak -E 's/\t/ /' file.txt Instead of replacing tab characters, it's replacing t characters. I've tried every ...
9
votes
5answers
6k views

pv for directory copy

I need to copy a very large directory (talking in terabytes here) and want to monitor the progress. I found that pv is a nice utility, but how can I use it for copying directories recursively? (pv ...
9
votes
1answer
13k views

Stuck process: is it a bad sign?

Sometimes a few process are in a stuck state. For example: PID COMMAND %CPU TIME #TH #WQ #POR #MREGS RPRVT RSHRD RSIZE VPRVT VSIZE PGRP PPID STATE 99357 plugin-container ...
9
votes
2answers
2k views

SSH LocalCommand on exit

In ~/.ssh/config you can use the LocalCommand directive to execute a local command whenever you connect to a remote machine via SSH. But how do I execute a command when I exit an SSH connection? It ...
9
votes
4answers
40k views

How to use ifconfig to show active interface only

By default ifconfig will show me all available interfaces , but what if I just want to display active ones? Like, en0 only in below. en0: ...
9
votes
1answer
228 views

OS X, bash: less works on open file descriptors, cat doesn't

In a bash script I'm working on (which has to run on Ubuntu and OS X), I need to redirect the output of hundreds of commands to a file. Rather than appending &>... to all of them, I simply do ...
9
votes
1answer
8k views

Why the value of VSIZE in top is different from the value of VSZ (Virtual set size) in ps?

I know VSZ in ps is for the total address space allocated for the app and is sometimes aliased as vsize (mentioned in man page of ps on linux), but what's the definition of VSIZE in top? This top ...
8
votes
10answers
48k views

Install rEFInd on OS X 10.10 Yosemite

I want to dual boot my macbook with Arch Linux and thus tried to install rEFInd using the install script, however, after install rEFInd doesn't seem to start at all? Anyone experienced the same issue ...
8
votes
4answers
3k views

Is there something like wine to run OSX apps on linux?

This question answers why Linux can't run OSX apps, but is there some application similar to Wine that allows one to do so?
8
votes
4answers
3k views

Directory size calculation difference

I need to get the size of directory in terminal for signing purposes. I'm using following command: du -s /path/to/dir I'm multiplying the result by traditional UNIX block size (512 bytes) and get ...
8
votes
1answer
18k views

chmod: What does the `+a` parameter mean?

I was following a tutorial and it told me to run sudo chmod +a "SOME_PARAMS" some/dir I was surprised to see that fail telling me chmod: invalid mode: `+a' So I wonder: What does the +a mode ...
8
votes
3answers
17k views

Creating a Bash script that will execute a program and if it exits without crashing, will run it again

I'd like to know the easiest way of creating a bash script that will run an app in MacOSX (it's a UNIX based system so I assumed this was the right place). wait for the program to exit. If the exit ...
8
votes
2answers
581 views

Prevent disk renumbering on reboot in OSX

I have 3 physical drives in my Mac Pro with OSX 10.6.4. Occasionally after rebooting the machine, the disk numbering changes such that the /dev/disk# does not reference the same drive as it did before ...
7
votes
3answers
614 views

wc command counts extra characters

cat > file Amy looked at her watch. He was late. The sun was setting but Jake didn’t care. wc file 1 16 82 file Can somebody explain why wc command returns 3 extra characters in this ...
7
votes
5answers
5k views

How to make bash put prompt on a new line after cat command?

What I get: host:~ user$ cat example.txt some texthost:~ stas$ What I want to get: host:~ user$ cat example.txt some text host:~ stas$ Is there a way I can make cat behave like this? I'm using ...
7
votes
5answers
6k views

How to copy all html files from a directory tree to a single directory?

I want to copy all the .html files in myDir and its subdirectories to ~/otherDir. Here's what I tried (it doesn't work): $ find myDir -name *.html -print | xargs -0 cp ~/otherDir usage: cp [-R [-H | ...
7
votes
6answers
3k views

How to grep-inverse-match and exclude “before” and “after” lines

Consider a text file with the following entries: aaa bbb ccc ddd eee fff ggg hhh iii Given a pattern (e.g. fff), I would like to grep the file above to get in the output: all_lines except ...
7
votes
2answers
649 views

Does OS X have its own line format?

Obviously there are at least two newline types: DOS and Unix. But does OS X have its own plaintext 'format'? I opened a text file in nano and was surprised to see: [ Read 26793 lines (Converted from ...
7
votes
3answers
770 views

How to permanently change both STDOUT and STDERR color to grey?

This question is similar to Can I configure my shell to print STDERR and STDOUT in different colors? But I am looking for a solution that will allow me to change both STDOUT and STDERR to ONE color. ...
7
votes
1answer
3k views

What is equivalent to Mac's purge in Linux?

In Mac I use purge to free up some memory. What is equivalent to it in Linux(Ubuntu Server)? apt-get install purge gave me nothing. If you are no familiar with Mac's purge here is it's man page: ...
7
votes
3answers
5k views

Grep_color on mac

I am trying to get my regex highlighted on mac using terminal. I have put this is my .profile: export GREP_COLOR='1;30;40' Nothing changes, so I added the same to my bash.profile still nothing, ...
7
votes
2answers
34k views

How to know when and which user logged into the system under Mac OS X? Last is not enough!

In Mac OS X, if I don't touch it for a while, it will lock the screen and one must use password to unlock it, but this kind of log in is not recorded by last command. I want to know if anybody tried ...
7
votes
1answer
3k views

Where to install applications

I'm a long-time Windows user in the middle of a multi-year personal migration to Linux-based development. On Windows when I installed an application it got put in the Program Files folder and I'd ...
7
votes
1answer
9k views

How do I start a virtual machine in background upon OSX system start?

I have a virtualbox machine on a OSX 10.9.2 host. I do not want to open VirtualBox everytime and start the machine there. Also, I do not need the the screen output as I will just ssh from OSX terminal ...
7
votes
1answer
4k views

Get the current volume level in OS X Terminal CLI?

I would like to check the current volume level from the CLI on my Mac. I know I can set it like this: osascript -e 'set volume <N>' But that doesn't seem to work when trying to get the ...
7
votes
2answers
6k views

Does Windows recognize Linux's symbolic links?

I was just wondering how a Windows system handles symbolic links. My best guess is that it will not recognize them, but I'm not entirely sure. Also, what do Macs do when confronted by one?
7
votes
2answers
3k views

What should I be aware of when installing Linux on a Mac?

I have a Macbook Pro and I am loving it, though I still miss my Linux box, there are many things I need which are not completely compatible with Mac OS X. I heard many stories about installing Linux ...
7
votes
2answers
859 views

How to use the SVN CLI effectively

How can I make myself more productive with the SVN CLI? I need to complete repetitive tasks like these: find modified files in directory commit only SOME of them selecting them somehow other then ...
7
votes
2answers
252 views

Hibernate and security considerations

How do Linux and OSX handle sensitive memory pages (e.g. cryptographic keys) when running OS is suspended to disk? If the memory image written is encrypted, how are its keys handled?
7
votes
1answer
4k views

How to persist ulimit settings in OSX Yosemite?

Previous question about doing this on Mavericks is here and the answers there don't seem to work on Yosemite. I want to enable core dump generation by default upon reboot. Executing ulimit -c ...
7
votes
2answers
710 views

How do I only undo pasted text in vim?

TL;DR; version - How do I undo text that was pasted in from my OS copy buffer without undoing other text that was typed in since I went into insert mode? Longer description: Put something in your ...
7
votes
2answers
2k views

emacs - paste text from clipboard without formatting

I am using Emacs 24 for MacOSX and having some problem with pasting code from clipboard to Emacs. The code that I selected usually already nicely formatted (with tab, ident, ...). However, when I ...
7
votes
2answers
473 views

Bash inside Vim not working properly

In MacVim I'm using Conque to run bash commands inside Vim. I have a problem with the text navigation while using Conque. If I'm at the end of a line of text and press down Alt← I skip a word to the ...
7
votes
1answer
1k views

Screen cuts off beginning of long command when accessed through bash history

I'm using the default versions of bash and screen in OS X Lion. When I'm in a screen session and I scroll back through the bash history and I come to a command that is long enough to wrap. I might ...
7
votes
1answer
342 views

in zsh, how do I hide the backslashes in the completion menu

On Mac OS X 10.6, zsh. I have set in .zshrc: setopt automenu …to get a completion menu below the prompt. When I type: cd <TAB> I see a completion menu with all directories that have spaces ...
7
votes
1answer
1k views

How do I increase the maximum swap space on Mac OS X? [closed]

On Mac OS X Yosemite 10.10.5, when I try to run a calculation that needs to allocate and use 128 GB of memory (it is a command line program written in C), the kernel kills my process with extreme ...
6
votes
1answer
22k views

access external hard drive to delete folder on terminal Mac

I want to delete a folder of portable hard drive on terminal in Mac. Are there any command line ?
6
votes
3answers
566 views

Any tips for surviving Terminal.app?

I've recently switched to using a Mac full-time, and am having trouble getting used to Terminal.app after years of loving gnome-terminal. I miss having URLs show up underlined, using alt+arrow to ...
6
votes
2answers
3k views

Tell if a folder/file is hidden in Mac OS X

I know you can set or unset the hidden flag of a folder/file by doing chflags hidden foo.txt and chflags nohidden foo.txt. But is there anyway of telling whether the folder/file is currently hidden ...
6
votes
2answers
233 views

What is causing `diff` to run `git diff`?

I'd like to use diff as described here and in the documentation I see when I type man diff. However, when I type diff, what I get is this: ~ ❯❯❯ diff usage: git diff --no-index <path> ...
6
votes
2answers
713 views

Zsh: Automatically modify executed command

I've recently installed grc (generic colorizer) to my system via MacPorts, giving me the ability to get colorized output for plenty of commands which by default don't support it (see screenshot ...
6
votes
1answer
5k views

how to remove quarantine from file permissions in os x

I downloaded a .pem file and my Mac OS X (10.8.2) added an @ sign at the end of the file permissions. This is causing file permission issues. I can't seem to remove the quarantine flag. I even tried ...