Author: Jeffrin

nc – TCP/IP swiss army knife

A UNIX Command Window I Server $nc -l -p 3333 hello hello how are you ? fine Window II client $nc 127.0.0.1 3333 hello hello how are you ? fine Explanation netcat is a simple unix utility which reads and writes data across network connections, using TCP or UDP protocol. Related Source Code Exposition doexec …

Read More

free – Display amount of free and used memory in the system

GNU command $free total used free shared buffers cached Mem: 507008 432908 74100 0 14700 186816 -/+ buffers/cache: 231392 275616 Swap: 1485972 0 1485972 $free -m total used free shared buffers cached Mem: 495 422 72 0 14 182 -/+ buffers/cache: 225 269 Swap: 1451 0 1451 $ Explanation Display amount of free and used …

Read More

tee – read from standard input and write to standard output and files

GNU Command $tee name my name is nice. my name is nice. $cat name my name is nice. $ Explanation Copy standard input to each FILE, and also to standard output. A special variant of the tee for the shell is called script and permits duplicating all input commands submitted to a shell into a …

Read More

stat – display file or file system status

GNU Command stat -f / $stat -f / File: “/” ID: bc427fdafb7b0541 Namelen: 255 Type: ext2/ext3 Block size: 4096 Fundamental block size: 4096 Blocks: Total: 18864769 Free: 16209639 Available: 15251363 Inodes: Total: 4792320 Free: 4684854 $ Explanation Display file or file system status. Related Source Code Exposition static bool do_statfs (char const *filename, bool terse, …

Read More

vmstat – Report virtual memory statistics

A UNIX Command . vmstat -m Cache Num Total Size Pages fat_inode_cache 23 23 688 23 fat_cache 102 102 40 102 isofs_inode_cache 0 0 1006 12 udf_inode_cache 23 23 712 23 fuse_request 0 0 632 25 fuse_inode 0 0 768 21 dm_crypt_io 0 0 152 26 kcopyd_job 0 0 368 22 dm_uevent 0 0 2608 …

Read More

ypdomainname – show or set the system’s NIS/YP domain name

commandline session $ypdomainname ypdomainname: Local domain name not set $ypdomainname beautifulwork.edu ypdomainname: you must be root to change the domain name $dnsdomainname Jeff $ypdomainname ypdomainname: Local domain name not set $sudo ypdomainname beautifulwork.edu $ypdomainname beautifulwork.edu $

Read More

backtrace for iceweasel related hangup

(gdb) bt #0 0x00007fc68928b99d in pthread_join (threadid=1404900385100136, thread_return=0x0) at pthread_join.c:89 #16 0x00007fc68773d8e8 in XRE_main (argc=, argv=, aAppData=) at nsAppRunner.cpp:3331 #17 0x00000000004024df in main (argc=1, argv=0x7fffaa9352c8) at nsXULStub.cpp:493

Read More

getopt – parse command options

commandline session $getopt hello — $getopt hello how are you ? — how are you 1 c h $getopt hello hello are you ? — hello are you 1 c h $getopt hello hello are yours ? — hello are yours 1 c h $getopt hello hello are yours what ? — hello are yours …

Read More

compilation error. libjingle

commandline session ../../talk/base/messagequeue.h: In constructor ‘talk_base::Message::Message()’: ../../talk/base/messagequeue.h:121: error: ‘memset’ was not declared in this scope i have failed to fix it until now.it did not compile sucessfully. a typical source is available here The document may have broken link.

Read More

head – output the first part of files

commandline session $sudo head /var/log/syslog Jan 5 20:10:05 debian syslogd 1.5.0#6.1: restart. Jan 5 20:10:05 debian anacron[1056]: Job `cron.daily’ terminated Jan 5 20:10:05 debian anacron[1056]: Normal exit (1 job run) Jan 5 20:12:14 debian acpid: client connected from 1055[0:0] Jan 5 20:12:14 debian acpid: 1 client rule loaded Jan 5 20:12:14 debian acpid: client connected …

Read More