Unix Tutorial

Recommendations

Info

Performance Tools: Unix provides following important tools to measure and fine tune Unix system performance: Command nice/renice Netstat Time Uptime Ps Vmstat Gprof Prof Top Description Run a program with modified scheduling priority Print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships Time a simple command or give resource usage System Load Average Report a snapshot of the current processes. Report virtual memory statistics Display call graph profile data Process Profiling Display system tasks You can use Manpage Help to check complete syntax for each command mentioned here. TUTORIALS POINT Simply Easy Learning
CHAPTER 28 Unix – System Logging Unix systems have a very flexible and powerful logging system, which enables you to record almost anything you can imagine and then manipulate the logs to retrieve the information you require. Many versions of UNIX provide a general-purpose logging facility called syslog. Individual programs that need to have information logged send the information to syslog. Unix syslog is a host-configurable, uniform system logging facility. The system uses a centralized system logging process that runs the program /etc/syslogd or /etc/syslog. The operation of the system logger is quite straightforward. Programs send their log entries to syslogd, which consults the configuration file /etc/syslogd.conf or /etc/syslog and, when a match is found, writes the log message to the desired log file. There are four basic syslog terms that you should understand: Term Facility Priority Selector Action Description The identifier used to describe the application or process that submitted the log message. Examples are mail, kernel, and ftp. An indicator of the importance of the message. Levels are defined within syslog as guidelines, from debugging information to critical events. A combination of one or more facilities and levels. When an incoming event matches a selector, an action is performed. What happens to an incoming message that matches a selector. Actions can write the message to a log file, echo the message to a console or other device, write the message to a logged in user, or send the message along to another syslog server. Syslog Facilities: Here are the available facilities for the selector. Not all facilities are present on all versions of UNIX. Facility auth authpriv Description Activity related to requesting name and password (getty, su, login) Same as auth but logged to a file that can only be read by selected users TUTORIALS POINT Simply Easy Learning
Page 1 and 2:
Unix Tutorial
Page 3 and 4:
ABOUT THE TUTORIAL Unix Tutorial UN
Page 5 and 6:
Renaming Directories: .............
Page 7 and 8:
Extended Shell Scripts: ...........
Page 9 and 10:
Example: ..........................
Page 11 and 12:
Trapping Signals: .................
Page 13 and 14:
The main concept that unites all ve
Page 15 and 16:
New UNIX password:******* Retype ne
Page 17 and 18:
CHAPTER 2 Unix File Management All
Page 19 and 20:
Displays all the files whose name s
Page 21 and 22:
4. Fourth Column: represents file n
Page 23 and 24:
CHAPTER 3 Unix Directories Adirecto
Page 25 and 26:
Creates the directories docs and pu
Page 27 and 28:
CHAPTER 4 Unix File Permission Setu
Page 29 and 30:
$ls -l testfile -rw-rwxrwx 1 amrood
Page 31 and 32:
The SUID and SGID bits will appear
Page 33 and 34:
Note - The shell initialization pro
Page 35 and 36:
The default secondary prompt is > (
Page 37 and 38:
CHAPTER 6 Java Basic Utilities So f
Page 39 and 40:
laserp-574 grace 82744 Nov 7 11:28
Page 41 and 42:
CHAPTER 7 Unix Pipes and Filters Yo
Page 43 and 44:
This pipe sorts all files in your d
Page 45 and 46:
The process runs in the foreground,
Page 47 and 48:
$kill -9 6738 Terminated Parent and
Page 49 and 50:
CHAPTER 9 Unix Communication When y
Page 51 and 52:
prompt on Turns prompt on. Dir List
Page 53 and 54:
No Plan. Check all the logged in us
Page 55 and 56:
~ ~ ~ ~ ~ ~ ~ ~ "testfile" [New Fil
Page 57 and 58:
Command CTRL+d CTRL+d CTRL+f CTRL+u
Page 59 and 60:
^G U U J Press CNTRL and G keys at
Page 61 and 62:
IMPORTANT: Here are the key points
Page 63 and 64:
POSIX shell ( sh) The different C-t
Page 65 and 66:
CHAPTER 12 Unix- Using Variables Av
Page 67 and 68:
NAME="Zara Ali" unset NAME echo $NA
Page 69 and 70:
Command-Line Arguments: The command
Page 71 and 72:
CHAPTER 14 Unix - Using Arrays Ashe
Page 73 and 74:
CHAPTER 15 Unix - Basic Operators T
Page 75 and 76:
val=`expr $b / $a` echo "b / a : $v
Page 77 and 78:
else echo "$a -ge $b: a is not grea
Page 79 and 80:
!= Checks if the value of two opera
Page 81 and 82:
] is true. -x file Check if file is
Page 83 and 84:
Right shift == String comparison fo
Page 85 and 86: -r file Checks if file is readable
Page 87 and 88: Example: #!/bin/sh a=10 b=20 if [ $
Page 89 and 90: There is only one form of case...es
Page 91 and 92: CHAPTER 17 Unix - Shell Loops Loops
Page 93 and 94: done This will produce following re
Page 95 and 96: 4) juice 5) appe 6) all 7) none #?
Page 97 and 98: CHAPTER 18 Unix - Loop Control So f
Page 99 and 100: 1 0 1 5 The continue statement: The
Page 101 and 102: \n new line \r carriage return \t h
Page 103 and 104: CHAPTER 20 Unix - Quoting Mechanism
Page 105 and 106: The Double Quotes: Try to execute t
Page 107 and 108: CHAPTER 21 Unix - IO Redirections M
Page 109 and 110: EOF 3 $ This is a simple lookup pro
Page 111 and 112: CHAPTER 22 Unix - Shell Functions F
Page 113 and 114: echo "Return value is $ret" This wo
Page 115 and 116: CHAPTER 23 Unix - Manpage Help All
Page 117 and 118: CHAPTER 24 Unix - Regular Expressio
Page 119 and 120: Try out the following address range
Page 121 and 122: sys:x:3:3:sys:/dev:/bin/sh sync:x:4
Page 123 and 124: [0-9] Matches a single number [a-zA
Page 125 and 126: (555)555-1213 (555)555-1214 (666)55
Page 127 and 128: dev /etc /lib /boot /home /mnt /pro
Page 129 and 130: $du -h /etc 5k /etc/cron.d 63k /etc
Page 131 and 132: CHAPTER 26 Unix - User Administrati
Page 133 and 134: $ groupdel developer This removes o
Page 135: CHAPTER 27 Unix - System Performanc
Page 139 and 140: The combination of facilities and l
Page 141 and 142: Unix - Signals and Traps CHAPTER 29
Page 143 and 144: Trapping these signals is quite eas
Page 145 and 146: CHAPTER 30 Unix - Useful Commands T
Page 147 and 148: Ispell Emacs ex, edit Emacs Emacs C
Page 149 and 150: Command Dbx Gdb Make Nm Size Strip
Page 151 and 152: Reset Reset terminal mode Script Ke
show all

Unix Tutorial

Create successful ePaper yourself

Delete template?

Save as template?