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5
votes
2answers
5k views

Linux : Major and Minor device numbers

What types of devices fall under the major device number category and what types of devices fall under the minor device number category. What is the real difference between the two categories?
4
votes
4answers
757 views

linux + how to ignore (filter) file with space

Sometimes a file name is created from a couple of names and space between each name as the following: $ touch "A B C" $ ls A B C <-- one file but has three words ! ...
2
votes
1answer
125 views

fdisk. What does the “free” partition mean?

I had two primary partitions (/dev/sda1 and /dev/sda2). Then I created an extended partition to segment it into logical partitions. After I had typed fdisk /dev/sda and n (add a new partition) the ...
2
votes
1answer
2k views

Ubuntu: wire network is not stable and must restart network-manager periodcally

I don't know why my wire network now is not stable. After a short time of using, maybe 30 minutes, 15 minutes or maybe just 2 minutes, my network is down. When my network is down, I must run this ...
1
vote
1answer
238 views

Reading encrypted partition with broken LVM2 inside?

I overwrote some LVM2 metadata in much the same way as Recovering overwritten LVM metadata . That is, I attempted to install Debian 6.0.7 on a system with existing encrypted volumes and LVM2 volumes. ...
3
votes
3answers
2k views

Colorize Bash Console Color

I need to be able to set my CentOS 6.4 bash prompt color to yellow. I've managed to find where to set this (.bashrc) and the ANSI color for yellow (\e[0;33m). I've setup my prompt as follows: ...
0
votes
2answers
94 views

Why is my Yellow Dog keyboard layout wrong? [closed]

I just installed Yellow Dog on my PowerBook G4, and it worked, and noticed my mac keyboard. Then, suddenly, the layout went wrong. Most keys don't do anything, and I have letters instead of arrow ...
0
votes
1answer
435 views

Understanding a XINU system call - getstk.c [closed]

I am having trouble conceptually understanding what is going on towards the end of this system call, and why. I understand the getstk.c method returns the highest memory address of available space, ...
1
vote
1answer
1k views

How to clone a read-only portion of /proc file system

The problem with reading /proc file system is that it is not atomic. I tried using a library (procfs in Python) that wishes to read it, but it has glitches about 5% of the time because the process ...
2
votes
2answers
110 views

Akonadi floods my .xsession-errors

I am seeing tons of these error in my .xsession-errors: krunner(8135)/libakonadi Akonadi::SessionPrivate::socketError: Socket error occurred: "QLocalSocket::connectToServer: Connection refused" ...
7
votes
4answers
358 views

Which data should be excluded from log files , error messages etc. if posted online?

What data should one erase from log files, error messages etc., if posting them as a screenshot so as not to expose sensitive information? As I have little knowledge about this topic, I can vividly ...
1
vote
2answers
746 views

Determine whether kernel built-in driver supports a device

I'm trying to find a way to accurately determine whether all the hardware on some system has a valid driver installed either via a kernel module or built-in to the kernel. I'm working with RHEL 5.5 ...
1
vote
1answer
1k views

How to run rtl8192cu driver in linux with kernel 3.8?

I have a trouble with usb WiFi dongle TPLink WN725N (rtl8192cu driver). Dongle it start, but cannot connect. Driver in official Realtek site support only 2.6.18~2.6.38 and 3.0.8 kernels. Is there a ...
2
votes
1answer
111 views

Deleting a pattern from a file and appending it to the end?

I have a log file which have contents like below: #SOME MORE DATA These switches don't have latest images : SWEs-elmPCI-A-01# #SOME MORE DATA These switches don't have latest images : ...
3
votes
1answer
2k views

How do I route different users over different OpenVPN tunnels in Linux?

The setup: I have multiple, static-key OpenVPN client/server configurations, labeled "client1", "client2", and "client3" with server/client IPs 10.10.1.1/10.10.1.2, 10.10.2.1/10.10.2.2, and ...
1
vote
4answers
185 views

How can i run a piece of code in background?

Can I run a piece of code in background instead of using another script. [sesiv@itseelm-lx4151 ~]$ cat ./testback2 #!/bin/bash start_time=$(date +%s) for i in {1..5} do ./testscript & done wait ...
0
votes
1answer
316 views

How to remove LUKS auto-unlock?

Unfortunately my drive unlocks automatically. This makes the whole encryption useless. How do I turn off this annoying feature on a specified drive (e.g. /dev/x) ? The cryptsetup command I've found ...
3
votes
0answers
305 views

Exynos 5 DVFS or turning off cores in Ubuntu - Scaling frequency for one of the cores only (dual core) (cpufreq)

I was wondering if there is possible to scale only one of the cpu cores in the A15 in Exynos 5 ? I have tried using e.g cpufreq-set -c 1 -f 500MHz, but both cores are set to the same frequency. When ...
0
votes
2answers
93 views

Executing a program according to the last modified date

I need to write a script which would execute some executables in a directory according to the last modified date. The oldest should run first. How do I do it? This is what I have done so far for f ...
4
votes
2answers
483 views

Install application to /usr/local

Some application that installs automatically such as Netbean, JDK often install to /usr/local and I run it by normal user (not root). But another application, just extract tar.gz file and run it. ...
10
votes
2answers
11k views

Installing a package locally to a user - best practices?

I want to install Git locally to a user on a RHEL server (I don't have root access) What would be your cleanest/ most organized way of installing software to a local user account? Installing ...
2
votes
1answer
466 views

Configure SSL Mutual (Two-way) Authentication

I was asked to do it "Configure SSL Mutual (Two-way) Authentication" and I don't know where to start or how to test it . server and many clients . they can access code on server only if they have a ...
1
vote
3answers
127 views

Does sed write to the file or give a sample output

when using sed with a file like this sed 's/a/o' fruits it gives the necessary output to the terminal but it does not change the contents in the file. How do I permanently change the file with the ...
0
votes
1answer
2k views

Can't load IA 32-bit .so on a IA 32-bit platform

I'm trying to install an 32_bit_application on CentOS (64-bit), while running the setup.bin file it return the following error Invocation of this Java Application has caused an ...
2
votes
2answers
694 views

Creating an Alias to Loopback Interface with an Arbitrary Name

I have an odd problem that seems simple enough but has evaded me thus far. I am attempting to support a legacy application that has a hard-coded ethernet device name ("eth0"). This hard-coding, I am ...
10
votes
2answers
10k views

wlan number assignment

How or where does Linux determine the assignment of a network device? Specifically, wlan0 or wlan1 for wireless USB devices. I plugged in a TP USB wireless a while ago, and it was assigned wlan0. I ...
9
votes
3answers
5k views

Why does rsync fail to copy files from /sys in Linux?

I have a bash script which uses rsync to backup files in Archlinux. I noticed that rsync failed to copy a file from /sys, while cp worked just fine: # rsync /sys/class/net/enp3s1/address /tmp ...
1
vote
1answer
338 views

Is there a list of NICs that work with linux?

I built a new computer and want to install Linux on it. I loaded a couple different flavors and they detect there is a NIC but it won't connect to the network. It looks like it tries and tries but ...
11
votes
1answer
12k views

How can I mount filesystems with > 4KB block sizes?

I have a 3TB hard disk pulled out of a WD Mybook Live NAS. The partition table is as follows: Model: ATA WDC WD30EZRS-11J (scsi) Disk /dev/sdb: 3001GB Sector size (logical/physical): 512B/4096B ...
1
vote
3answers
216 views

string and number comparsion in bash in test statements?

I am not sure about this comparison i am doing: if [ "$exit_status" -eq 0 ];then #some statements fi is this correct way of comparing numbers or quotes make the variable exit_status a ...
4
votes
0answers
78 views

why . and .. are listed when ls -a command executed? [duplicate]

When I execute the ls -a command, all files and folders in that directory listed, as well as . and .. are listed too. Why is that? Are they a file or folder?
6
votes
2answers
776 views

Does AppArmor decrease the system performance?

Does AppArmor decrease the system performance? I have a slow system (900 MHz CPU) which has AppArmor because it was installed by default I would like to know if it become faster if I remove it, ...
1
vote
1answer
3k views

Multiple option arguments using getopts in bash

I am trying to process command line arguments using getopts in bash. One of the requirements is for the processing of an arbitrary number of option arguments (without the use of quotes). 1st example ...
5
votes
1answer
1k views

How does irqbalance determine which package to use?

irqbalance --debug shows the following: Package 0: Core 0, 2, 4, 6, 8, 10, 12, 14 Package 1: Core 1, 3, 5, 7, 9, 11, 13 When I run network applications, it seems like IRQs are being handled by ...
1
vote
0answers
3k views

How to install precompiled ath9k driver?

I have a Ubuntu and I have cross compiled an ath9k driver for an ARM architecture. The problem is a can't make the install work as I want to work. README says the following: Building for external ...
3
votes
2answers
91 views

How can a user restrict their own group rights without being root?

How can I change my user rights from rwx to r-x at the group level? I'm trying to ensure that I cannot touch any data belonging to other users when I am developing and debugging my scripts. Once I've ...
1
vote
1answer
523 views

Do kernel counters for jiffies in state exist in Linux?

I am looking to get time/jiffie stats on the state of a daemon process. The states I'm referring to are mentioned in the Linux Kernel Proc Filesystem document. Running, Sleeping, uninterruptible ...
2
votes
0answers
110 views

How to set up remote graphical sessions on CentOs?

Trying to set up a Centos 6 server configuration where we can automate the running of an application that uses Selenium. In this case, ideally, we should be able to: Create a graphical session ...
1
vote
2answers
508 views

Does linux modules/drivers belong to kernal space or user space

Some articles say that modules/drivers belong to kernel space as it take part in forming the kernel; (reference: http://www.freesoftwaremagazine.com/articles/drivers_linux) While others say that ...
3
votes
1answer
2k views

How to access u boot environment from linux?

How can I access and change the u-Boot env variables in linux. Using the u-boot/tools/env directory in u boot directory: u-boot$ make env Which created the executable file fw_printenv. I copied ...
2
votes
2answers
505 views

Why read() is slower than getc()? [closed]

Why is read slower than getc? For example, this: for (;;) { chr++; amr=read(file1, &wc1, 1); amr2=read(file2, &wc2, 1); if (wc1 == wc2) { if ...
3
votes
1answer
488 views

Confirm before exit the command-prompt

I am trying to have a confirmation message every time I type exit command in the command-prompt. To do this, I have tried to use trap in .bashrc file but it seem like trap is not a solution as it run ...
4
votes
2answers
4k views

Measure disk IO latencies of a running process

I'm trying to measure the disk IO latencies of a running process to make a histogram. I could do this with DTrace in operating systems that provide it (e.g. as in this Joyent paper), but my ...
3
votes
1answer
533 views

How to create rootfs for user mode Linux on Fedora 18?

I want to create a rootfs to be used with an UML kernel and be able to use the internet. I was using febootstrap with packages: bash, coreutils, net-tools, iputils. After using ...
8
votes
0answers
216 views

how to get exit status from the command before the last [duplicate]

I have solaris machine ( solaris 10 ) please Look on the following simple commands (haconf -makerw | grep -iq "Cluster already writable") # haconf -makerw VCS WARNING V-16-1-10364 Cluster ...
3
votes
1answer
1k views

How to guarantee writes are physically committed before reported completed?

When my system boots, as it probes the external, USB-attached hard drive, I get the message Assuming drive cache: write through in the dmesg output, tagged with the device name of the external drive. ...
4
votes
3answers
12k views

Portable Firefox Linux

I've installed latest firefox linux-x86_64 from ftp.mozilla.com on a usb device and created a new profile file with the -P command. Unfortunately, the application does not recognize the flash plugin ...
0
votes
1answer
54 views

What is this feature in Linux 'to highlight characters' with QT?

Recently I came across this site. It says, in Linux with QT, it is possible 'to highlight characters' by pressing ShiftCtrl {Left,Right} or Shift {Left,Right}. Could somebody please explain this ...
1
vote
1answer
499 views

ixgbe: increase rx performance

I have an Intel 82598EB 10GBE NIC. I need to receive traffic without packet loss. Data rate is 4-5 Gbps, packet size is 1500-9600 bytes. I had already configured smb and irq affinity. I also tried ...
6
votes
1answer
2k views

vi[m] read range of lines from another file

On Linux, editing file_B in vim I want to add line 10-25 from file_A. Example: One has a whole set of HTML-Documents with quite the same header and yes, one could create a template and start from ...