Category Archives: operating system

BusyBox – The Swiss Army Knife of Embedded Linux

UNIX Command $dpkg -L busybox /. /bin /bin/busybox /usr /usr/share /usr/share/man /usr/share/man/man1 /usr/share/man/man1/busybox.1.gz /usr/share/doc /usr/share/doc/busybox /usr/share/doc/busybox/copyright /usr/share/doc/busybox/changelog.Debian.gz $mount /dev/sda1 on / type ext3 (rw,errors=remount-ro,commit=0) tmpfs on /lib/init/rw type tmpfs (rw,nosuid,size=5242880,mode=755,size=5242880,mode=755) tmpfs on /run type tmpfs (rw,noexec,nosuid,size=10%,mode=755,size=10%,mode=755) proc on /proc type proc (rw,noexec,nosuid,nodev) sysfs on /sys type sysfs (rw,noexec,nosuid,nodev) udev on /dev type tmpfs (rw,mode=0755) tmpfs …

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fs: Make write(2) interruptible by a fatal signal

Kernel Space linux-fsdevel@vger.kernel.org : Currently write(2) to a file is not interruptible by any signal. Sometimes this is desirable, e.g. when you want to quickly kill a process hogging your disk. Also, with commit 499d05ecf990 (“mm: Make task in balance_dirty_pages() killable”), it’s necessary to abort the current write accordingly to avoid it quickly dirtying lots …

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What is a TASK_KILLABLE state in Linux ?

ABOUT TASK_KILLABLE state TASK_KILLABLE sleeping state. Like most versions of Unix, Linux has two fundamental ways in which a process can be put to sleep. A process which is placed in the TASK_INTERRUPTIBLE state will sleep until either (1) something explicitly wakes it up, or (2) a non-masked signal is received. The TASK_UNINTERRUPTIBLE state, instead, …

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udev – Linux dynamic device management

ABOUT UDEV udev – Linux dynamic device management udev (userspace /dev) is a device manager for the Linux kernel CONFIG FILE RELATED # do not edit this file, it will be overwritten on update ACTION==”remove”, GOTO=”cdrom_end” SUBSYSTEM!=”block”, GOTO=”cdrom_end” KERNEL!=”sr[0-9]*|xvd*”, GOTO=”cdrom_end” ENV{DEVTYPE}!=”disk”, GOTO=”cdrom_end” # unconditionally tag device as CDROM KERNEL==”sr[0-9]*”, ENV{ID_CDROM}=”1″ # media eject button pressed …

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What is a dirty inode and what are dirty bytes ?

What is a Dirtied inode It is a common computer term that data in a cache is “clean” when it has been synchronized, and “dirty” when it is different. A dirty inode has had new data written into it but it has not been written to disk. source : http://serverfault.com/questions/56374/dirtied-inode dirty_inode: this method is called …

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block_dump enables block I/O debugging when set to a nonzero value

When this flag is set, Linux reports all disk read and write operations that take place, and all block dirtyings done to files. This makes it possible to debug why a disk needs to spin up, and to increase battery life even more. The output of block_dump is written to the kernel output, and it …

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nohup – run a command immune to hangups, with output to a non-tty

A UNIX Command $nohup ls < /dev/null nohup: appending output to `nohup.out' $cat nohup.out Desktop Downloads JohnySagariga LeanBiz.zip nohup.out $ls Desktop Downloads JohnySagariga LeanBiz.zip nohup.out $ $nohup top < /dev/null nohup: appending output to `nohup.out' $cat nohup.out Desktop Downloads JohnySagariga LeanBiz.zip nohup.out top: failed tty get $nohup top < /dev/ nohup: appending output to `nohup.out' …

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gold – The GNU ELF linker

In software engineering, gold is a linker for ELF files. It became an official GNU package and was added to binutils in March 2008[1] [2] and first released in binutils version 2.19. gold was developed by Ian Lance Taylor and a small team at Google.[3] The motivation for writing gold was to make a linker …

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