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Created by voodoo on December 08, 2011 08:52:40
Last update: December 08, 2011 08:52:40
I don't know if there's a fool proof way to find out which Linux distro you are running on, but here are some ways you can try:
cat /proc/version
cat /etc/issue
cat /etc/*release
lsb_release -a
Results on Ubuntu 11.10 oneiric:
$ cat /proc/version
Linux version 3.0.0-13-gene...
Results on Red Hat Enterprise Server:
$ cat /proc/version
Linux version 2.6.18-128.1....
Created by voodoo on June 14, 2011 08:10:42
Last update: June 14, 2011 08:10:42
The command " ifconfig -a " does not list the DNS servers. Use " cat /etc/resolv.conf " to look at the DNS server configuration. It works for DHCP configured network interfaces also.
$ cat /etc/resolv.conf
# Generated by NetworkMa...
If no DNS server is configured:
$ cat /etc/resolv.conf
# Generated by NetworkMa...
Created by freyo on October 29, 2010 18:02:41
Last update: October 29, 2010 18:04:02
The output from cat /proc/meminfo looks like this (enter the shell with abd shell ):
# cat /proc/meminfo MemTotal: 94096 kB... To quote hackbod from stackoverflow : Finally there is the command "adb shell cat /proc/meminfo" that gives a summary of the overall memory usage of the system. There is a lot of data here, only the first few numbers worth discussing (and the remaining ones understood by few people, and my questions of those few people about them often resulting in conflicting explanations). These are the meanings of the first five rows: Term Meaning MemTotal The total amount of memory available to the kernel and user space (often less than the actual physical RAM of the device, since some of that RAM is needed...
Created by voodoo on July 30, 2010 14:53:33
Last update: July 30, 2010 14:54:52
The -d switch for cURL sends HTTP POST with data from the command line. To verify the data being posted, this is a CGI script that echos the data back:
#!C:/perl/bin/perl.exe ## ## echo -- echos ... Examples: POST data from command line: C:\>curl -d input1=value1^&input1=value2 http://lo... POST data from stdin (with @ before the - symbol): C:\>curl -d @- http://localhost/cgi-bin/echo.pl ... POST data from a file (with @ before the - symbol and input redirect): C:\tmp>cat data.txt abcd 1234 xyz ... For some reason, @ with file name didn't work as expected: C:\tmp>curl -d @data.txt http://localhost/cgi-bin/... One thing to notice is that cURL removes the new line characters when posting (thus the echo back is only one line instead of three). This can...
Created by voodoo on June 17, 2010 16:02:07
Last update: June 17, 2010 16:03:05
Use the uname command to display the SunOS version:
$ uname -a
SunOS STAWOW1 5.10 Generic_142900-01...
I can't find a command to display Solaris version. But the /etc/release file gives version information:
$ cat /etc/release
Solar...
This is a mapping of SunOS versions to Solaris versions:
SunOS Version Solaris Version
SunOS 5.4 Solaris 2.4
SunOS 5.5 Solaris 2.5
SunOS 5.5.1 Solaris 2.5.1
SunOS 5.6 Solaris 2.6
SunOS 5.7 Solaris 7
SunOS 5.8 Solaris 8
SunOS 5.9 Solaris 9
SunOS 5.10 Solaris 10
Reference:
SUN Solaris Unix Commands and Scripts
Created by Dr. Xi on December 05, 2009 20:12:16
Last update: December 05, 2009 20:46:45
It's quite easy for Perl to open a pipe and read from it:
$file = "nospace.txt";
open(IN, "cat $file |") ...
But the code breaks when the file name contains a space:
# This does not work!
$file = "yes space.txt";
...
On Windows, these don't work either:
# This does not work!
$file = "yes space.txt";
...
You need to use a technique called Safe Pipe Opens :
$file = "yes space.txt";
$prog = "cat";
...
Created by Dr. Xi on September 10, 2008 15:51:42
Last update: November 26, 2008 21:14:46
Variable Description SET AUTO [COMMIT] {ON | OFF | IMM [EDIATE] | n} Controls when Oracle Database commits pending changes to the database. SET CMDS [EP] {; | c | ON | OFF} Sets the non-alphanumeric character used to separate multiple SQL*Plus commands entered on one line to c. SET CON [CAT] {. | c | ON | OFF} Sets the character you can use to terminate a substitution variable reference if you wish to immediately follow the variable with a character that SQL*Plus would otherwise interpret as a part of the substitution variable name. SET ECHO {ON | OFF} Controls whether the START (@) command lists each command in a script as the command is executed. SET EDITF [ILE] file_name[.ext] Sets the default filename...
Created by Dr. Xi on October 06, 2008 22:48:08
Last update: October 06, 2008 22:50:11
A first attempt would be to create an input file like this:
userid password shell_command1 shell_... and feed the lines to the telnet client: cat telnet_input.txt | telnet remote_host #... However, you'll learn soon enough that it doesn't work. You get output like this: Trying 192.168.159.128... Connected to bash... What's happening? The telnet client depleted all input before the remote host had a chance to respond. Since there's no more input, the telnet client initiated to close the connection. Adding a delay between the commands makes it work: (echo userid sleep 10 echo password ... How much time to sleep between commands is just guesswork. You can use Expect to provide more control over the automated session: #!/usr/bin/expect # timeout script aft......
Created by Dr. Xi on December 12, 2007 20:30:01
Last update: December 12, 2007 20:32:23
This is a script to tail a log file through the web browser. It uses AJAX, apache web server, mod_python, UNIX utilities tail (requires the --lines switch) and wc . The log file may reside on the web server or any other host accessible from the web server through SSH.
Although it's written in python, it should be easy to port to other languages such as Perl.
Apache httpd.conf :
LoadModule python_module modules/mod_python.so
...
Python script:
import time, os
from os.path import basename
...
Created by Dr. Xi on June 01, 2007 18:00:58
Last update: June 01, 2007 18:00:58
Use the cut command to select specific fields or columns from a file:
cut -d: -f1,5 /etc/passwd # select usern...
Created by Dr. Xi on May 31, 2007 02:19:55
Last update: May 31, 2007 02:19:55
The cat command is probably one of the most elementary commands on Unix. Here are some uses of cat that you may find interesting.
cat file1 file2 file3 > allfiles # combine ...