vdir – list directory contents

A UNIX Command $vdir symmel/ total 20 drwxr-xr-x 2 jeffrin jeffrin 4096 Jul 27 01:11 Docs -rw-r–r– 1 jeffrin jeffrin 88 Jul 25 00:57 kernel_start.asm -rw-r–r– 1 jeffrin jeffrin 78 Jul 25 00:57 kernel_start.s drwxr-xr-x 10 jeffrin jeffrin 4096 Jul 25 00:57 linux drwxr-xr-x 2 jeffrin jeffrin 4096 Jul 26 23:55 loader -rw-r–r– 1 jeffrin …

write — send a message to another user

A UNIX Command $bsd-write jeffrin 8 bsd-write: jeffrin is not logged in on 8 $bsd-write jeffrin tty8 bsd-write: jeffrin has messages disabled on tty8 $mesg y $bsd-write jeffrin tty8 bsd-write: jeffrin has messages disabled on tty8 $w 20:08:58 up 23 min, 3 users, load average: 0.02, 0.15, 0.16 USER TTY FROM LOGIN@ IDLE JCPU PCPU …

skill, snice – send a signal or report process status

A UNIX Command $skill Usage: skill [signal to send] [options] process selection criteria Example: skill -KILL -v pts/* The default signal is TERM. Use -l or -L to list available signals. Particularly useful signals include HUP, INT, KILL, STOP, CONT, and 0. Alternate signals may be specified in three ways: -SIGKILL -KILL -9 General options: …

parameter tcp_retries1

A UNIX Parameter $cat /proc/sys/net/ipv4/tcp_retries1 3 $echo 4 > /proc/sys/net/ipv4/tcp_r Parameter Definition This value influences the time, after which TCP decides, that something is wrong due to unacknowledged RTO retransmissions, and reports this suspicion to the network layer. RFC 1122 recommends at least 3 retransmissions, which is the default. Parameter Code Internals snippet 1 { …

hcitool – configure Bluetooth connections

A UNIX Command $hcitool hcitool – HCI Tool ver 4.89 Usage: hcitool [options] [command parameters] Options: –help Display help -i dev HCI device Commands: dev Display local devices inq Inquire remote devices scan Scan for remote devices name Get name from remote device info Get information from remote device spinq Start periodic inquiry epinq Exit …

basename – strip directory and suffix from filenames

A UNIX Command $basename basename: missing operand Try `basename –help’ for more information. $basename /usr/bin/ bin $basename /usr/ usr $ $basename /usr/bin/less less $basename /usr/include/ma malloc.h math.h $basename /usr/include/math.h math.h $basename /usr/include/math.h . math.h $basename /usr/include/math.h .h math $basename /usr/lib/libgccpp.so.1 libgccpp.so.1 $basename /usr/lib/libgccpp.so.1 .1 libgccpp.so $ UNIX Explanation `basename’ removes any leading directory components from …

grog – guess options for groff command

A UNIX Command $groff /usr/share/man/man7/pipe.7 | more %!PS-Adobe-3.0 %%Creator: groff version 1.21 %%CreationDate: Fri Jul 15 18:18:46 2011 %%DocumentNeededResources: font Times-Roman %%+ font Times-Bold %%+ font Times-Italic %%DocumentSuppliedResources: procset grops 1.21 0 %%Pages: 1 %%PageOrder: Ascend %%DocumentMedia: Default 595 842 0 () () %%Orientation: Portrait %%EndComments %%BeginDefaults %%PageMedia: Default %%EndDefaults %%BeginProlog %%BeginResource: procset grops 1.21 …

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 …

pwdx – report current working directory of a process

A UNIX Command $pwdx 3805 1413 1412 1799 1009 2002 3805: /home/jeffrin 1413: Permission denied 1412: Permission denied 1799: Permission denied 1009: Permission denied 2002: Permission denied $ $sudo pwdx 3805 1413 1412 1799 1009 2002 [sudo] password for jeffrin: 3805: /home/jeffrin 1413: / 1412: /var/lib/mysql 1799: / 1009: / 2002: / $ UNIX Explanation …