| command |
description |
| date |
Shows the current system's date & time.
[email protected]:~$ date
Mon, Apr 6, 2015 9:47:34 PM
|
| whatis |
This command shows the short description (definition) of a command.
[email protected]:~$ mkdir --help
|
| CMD --help |
This command shows the command’s help with the description and their options.
[email protected]:~$ mkdir --help
Usage: mkdir [OPTION]... DIRECTORY...
Create the DIRECTORY(ies), if they do not already exist.
Mandatory arguments to long options are mandatory for short options too.
-m, --mode=MODE set file mode (as in chmod), not a=rwx - umask
-p, --parents no error if existing, make parent directories as needed
-v, --verbose print a message for each created directory
-Z set SELinux security context of each created directory
to the default type
--context[=CTX] like -Z, or if CTX is specified then set the SELinux
or SMACK security context to CTX
--help display this help and exit
|
| man CMD |
This command shows the manual of command or function.
[email protected]:~$ man mkdir
MKDIR(1) User Commands MKDIR(1)
NAME
mkdir - make directories
SYNOPSIS
mkdir [OPTION]... DIRECTORY...
DESCRIPTION
Create the DIRECTORY(ies), if they do not already exist.
Mandatory arguments to long options are mandatory for short options
too.
-m, --mode=MODE
set file mode (as in chmod), not a=rwx - umask
........
|
| whoami |
This command displays the name of the current user (who is logged on).
[email protected]:~$ whoami
ih
|
| who am i |
This command displays the name of the logged on users with terminal name and logged on time.
[email protected]:~$ who am i
ih pts/1 2015-04-06 22:17
..
..
|
| who |
This command displays the information about all logged in users with terminal, time etc.
[email protected]:~$ who
ih pts/1 2015-04-06 22:17
mike pts/2 2015-04-06 22:19
|
| uptime |
This command tells how long system has been running.
[email protected]:~$ uptime
19:20:35 up 1:09, 2 users, load average: 0.05, 0.12, 0.10
here,
19:20:35 - is current system time.
1:09 - system running time.
|
| pwd |
Stands for "print working directory", is used to display current working direcotry, inwhich you are.
[email protected]:~$ pwd
/home/ih
|
| w |
Shows the login name os the user, who is online |
| logout |
Logouts from the current login. |
| cat /proc/cpuinfo |
Displays the cpu information.
$ cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Core(TM)2 Duo CPU T6600 @ 2.20GHz
stepping : 10
cpu MHz : 2195.000
cache size : 2048 KB
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae ...
TLB size : 0 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:
processor : 1
vendor_id : GenuineIntel
cpu family : 6
model : 23
model name : Intel(R) Core(TM)2 Duo CPU T6600 @ 2.20GHz
stepping : 10
cpu MHz : 2195.000
cache size : 2048 KB
fpu : yes
fpu_exception : yes
cpuid level : 13
wp : yes
flags : fpu vme de pse tsc msr pae mce cx8...
TLB size : 0 4K pages
clflush size : 64
cache_alignment : 64
address sizes : 36 bits physical, 48 bits virtual
power management:
|
| cat /proc/meminfo |
Displays the memory information.
$ cat /proc/meminfo
MemTotal: 3105660 kB
MemFree: 1520568 kB
HighTotal: 0 kB
HighFree: 0 kB
LowTotal: 3105660 kB
LowFree: 1520568 kB
SwapTotal: 1245184 kB
SwapFree: 961652 kB
|
| lscpu |
This commands shows the CPU process unit related information such as architecture, cpu mode, Byte Order, CPU(s) core, Vednor Id etc. |
| lshw |
Stands for "list hardware". This command lists the detailed and brief information about the multiple hardware such as cpu, memory, usb controllers, disks etc. It displays the information from the different /proc files. |
| hwinfo |
Another utility that shows the detailed and brief information about the multiple hardwares, it displays the more & detailed information than lshw command. |
| lsusb |
Stands for “list USB”. It shows the detailed & brief information about the USB controllers and connected USB(s) devices. |
| lsblk |
Stands for “list Block”. It shows the detailed & brief information about the installed block device drivers. |
| df |
It shows the disk space of the file system. |
| free |
It shows the total, used and free RAM size of the system. |
| mount |
It shows the mounted file systems. |