mirror of
https://github.com/LCTT/TranslateProject.git
synced 2025-01-25 23:11:02 +08:00
20131203-3 选题
This commit is contained in:
DeadFire
parent
d65cfa97b8
commit
23a33849d1
185
sources/10 Lesser Known Effective Linux Commands – Part IV.md
Normal file
185
sources/10 Lesser Known Effective Linux Commands – Part IV.md
Normal file
@ -0,0 +1,185 @@
|
||||
10 Lesser Known Effective Linux Commands – Part IV
|
||||
================================================================================
|
||||
Continuing the **Lesser Known** series, this fourth article of the series will let you know some useful **funny** and **animated** commands. Here we go into the practical session, without much theory.
|
||||
|
||||
|
||||
|
||||
- [11 Lesser Known Useful Linux Commands – Part I][1]
|
||||
- [10 Lesser Known Linux Commands – Part 2][2]
|
||||
- [10 Lesser Known Commands for Linux – Part 3][3]
|
||||
|
||||
In the fourth article of this series which includes few other lesser known Linux commands, worth knowing. Might be you’re already aware of these commands, no doubt you’re an experienced Linux user and loves exploration.
|
||||
|
||||
### 32. strace Command ###
|
||||
|
||||
The **strace** is a debugging tool which is used primarily for troubleshooting purpose in Linux. It might not be installed by default in your system and you may need to **apt** or **yum** the required package.
|
||||
|
||||
Trace a command execution using strace command:
|
||||
|
||||
root@tecmint [~]# strace pwd
|
||||
|
||||
#### Sample Output ####
|
||||
|
||||
execve("/bin/pwd", ["pwd"], [/* 29 vars */]) = 0
|
||||
brk(0) = 0x728000
|
||||
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0df2000
|
||||
access("/etc/ld.so.preload", R_OK) = -1 ENOENT (No such file or directory)
|
||||
open("/etc/ld.so.cache", O_RDONLY) = 3
|
||||
fstat(3, {st_mode=S_IFREG|0644, st_size=38427, ...}) = 0
|
||||
mmap(NULL, 38427, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7f29b0de8000
|
||||
close(3) = 0
|
||||
open("/lib64/libc.so.6", O_RDONLY) = 3
|
||||
read(3, "\177ELF\2\1\1\3\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\360\355\1I;\0\0\0"..., 832) = 832
|
||||
fstat(3, {st_mode=S_IFREG|0755, st_size=1922152, ...}) = 0
|
||||
mmap(0x3b49000000, 3745960, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_DENYWRITE, 3, 0) = 0x3b49000000
|
||||
mprotect(0x3b4918a000, 2093056, PROT_NONE) = 0
|
||||
mmap(0x3b49389000, 20480, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_DENYWRITE, 3, 0x189000) = 0x3b49389000
|
||||
mmap(0x3b4938e000, 18600, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x3b4938e000
|
||||
close(3) = 0
|
||||
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de7000
|
||||
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de6000
|
||||
mmap(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x7f29b0de5000
|
||||
....
|
||||
|
||||
The **strace** command accepts a lot of arguments and have many options. Refer to man page for detailed information.
|
||||
|
||||
### 33. disown -a && exit Command ###
|
||||
|
||||
Most of the system administrators use [screen command][4] to control jobs running in the terminal background. Let’s say if you having a long running job and want to **detach** from the terminal, you use screen command to do it. But what if you don’t know how to use screen, here comes disown command to rescue.
|
||||
|
||||
The disown command is used to run the jobs continuously in the background even after you closing the terminal session. The syntax of the disown command is:
|
||||
|
||||
root@tecmint [~]# Command; disown -a && exit
|
||||
|
||||
To detach again the long running job in the terminal, use the **jobs** command to find the job number and then use disown **%n** where **n** is the job number. To verify actually the job is running use **ps** or [top command][5]. The **nohup** command is an alternative to the disown command.
|
||||
|
||||
### 34. getconf LONG_BIT Command ###
|
||||
|
||||
The above command shows your machine architecture if it is **32** bit or **64** bit?
|
||||
|
||||
root@tecmint [~]# getconf LONG_BIT
|
||||
|
||||
32
|
||||
|
||||
- [Download Linux Command Line Cheat Sheet][5]
|
||||
|
||||
### 35. Display Date on the Terminal ###
|
||||
|
||||
The below command is a combination of several commands, better say it a script. For a person working at shell or terminal, without GUI seeing current system date is tedious job. You have to type ‘**date**‘ command to check today’s date.
|
||||
|
||||
Just execute the below command on you prompt and see the **date** and **time** on the above right corner of terminal.
|
||||
|
||||
root@tecmint [~]# while sleep 1;do tput sc;tput cup 0 $(($(tput cols)-29));date;tput rc;done &
|
||||
|
||||
|
||||
|
||||
### 36. convert Command ###
|
||||
|
||||
While writing tutorial, I usually need to produce output, many a times in image format. The above command combination does this for me. Say I need the output of tree command (for **/etc/x11** directory) in image format. What I did at terminal was:
|
||||
|
||||
root@tecmint:/etc/X11# tree | convert label:@- /home/avi/tree.png
|
||||
|
||||
The output of the above command can be seen at the specified location (here, home directory of mine) with the file name specified as **tree.png**.
|
||||
|
||||
### 37. watch -t -n1 “date +%T|figlet” ###
|
||||
|
||||
Remember our description of “**figlet**” command in our earlier article “[20 Funny Commands of Linux][7]”. This command was very cool, this time we will be pipelining ‘**figlet**‘ to show animated digital clock in the terminal.
|
||||
|
||||
Just check-out yourself, remember you must have **figlet** installed on the system, do **apt** or **yum** to install the required package.
|
||||
|
||||
root@tecmint [~]# watch -t -n1 "date +%T|figlet"
|
||||
|
||||
#### Sample Output ####
|
||||
|
||||
_ ___ ____ ___ _____ _ _ Fri Nov 29 10:29:34 GMT
|
||||
/ |/ _ \ _|___ \ / _ \ _|___ /| || |
|
||||
| | | | (_) __) | (_) (_) |_ \| || |_
|
||||
| | |_| |_ / __/ \__, |_ ___) |__ _|
|
||||
|_|\___/(_)_____| /_/(_)____/ |_|
|
||||
|
||||
### 38. host and dig Commands ###
|
||||
|
||||
Although “**host**” and “**dig**” command is not that much lesser known, still not very frequently used. The host command is **DNS** lookup utility.
|
||||
|
||||
root@tecmint [~]# host www.google.com
|
||||
|
||||
www.google.com has address 173.194.66.147
|
||||
www.google.com has address 173.194.66.105
|
||||
www.google.com has address 173.194.66.99
|
||||
www.google.com has address 173.194.66.104
|
||||
www.google.com has address 173.194.66.106
|
||||
www.google.com has address 173.194.66.103
|
||||
www.google.com has IPv6 address 2a00:1450:400c:c03::68
|
||||
|
||||
|
||||
root@tecmint [~]# dig www.google.com
|
||||
|
||||
; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6_4.6 <<>> www.google.com
|
||||
;; global options: +cmd
|
||||
;; Got answer:
|
||||
;; ->>HEADER<
|
||||
|
||||
### 39. dstat Command ###
|
||||
|
||||
The **dstat** is a versatile tool, that generates statistics relating to system resource. By default your system might not have ‘**dstat**‘ installed. Do a **apt** or **yum** to install ‘**dstat**‘ before using this very colorful and description system resource generator.
|
||||
|
||||
root@tecmint [~]# dstat
|
||||
|
||||
|
||||
|
||||
### 40. bind -p Command ###
|
||||
|
||||
The ‘**bind -p**‘ command will show all the shortcuts available for **BASH** shell.
|
||||
|
||||
root@tecmint [~]# bind -p
|
||||
|
||||
#### Sample Output ####
|
||||
|
||||
"\C-g": abort
|
||||
"\C-x\C-g": abort
|
||||
"\e\C-g": abort
|
||||
"\C-j": accept-line
|
||||
"\C-m": accept-line
|
||||
# alias-expand-line (not bound)
|
||||
# arrow-key-prefix (not bound)
|
||||
# backward-byte (not bound)
|
||||
"\C-b": backward-char
|
||||
"\eOD": backward-char
|
||||
"\e[D": backward-char
|
||||
"\e!": complete-command
|
||||
"\e/": complete-filename
|
||||
"\e@": complete-hostname
|
||||
"\e{": complete-into-braces
|
||||
"\e~": complete-username
|
||||
"\e$": complete-variable
|
||||
# copy-backward-word (not bound)
|
||||
# copy-forward-word (not bound)
|
||||
# copy-region-as-kill (not bound)
|
||||
....
|
||||
....
|
||||
|
||||
### 41. touch /forcefsck ###
|
||||
|
||||
The above command will create an empty folder '**forcefsck**', under root directory. This will force Linux System to check the file system on the very next boot.
|
||||
|
||||
root@tecmint [~]# touch /forcefsck
|
||||
|
||||
hat’s all for Now. You People are loving these ‘**Lesser Known Commands**‘ and hence we are continuing the series, the next article of this series will be available very soon.
|
||||
|
||||
Till then stay tuned and connected to **Tecmint**. Don’t forget to give your valuable feedback in our comment section. Do a favor to us, Like and share us and help us spread.
|
||||
|
||||
--------------------------------------------------------------------------------
|
||||
|
||||
via: http://www.tecmint.com/10-lesser-known-effective-linux-commands-part-iv/
|
||||
|
||||
译者：[译者ID](https://github.com/译者ID) 校对：[校对者ID](https://github.com/校对者ID)
|
||||
|
||||
本文由 [LCTT](https://github.com/LCTT/TranslateProject) 原创翻译，[Linux中国](http://linux.cn/) 荣誉推出
|
||||
|
||||
[1]:http://www.tecmint.com/11-lesser-known-useful-linux-commands/
|
||||
[2]:http://www.tecmint.com/10-lesser-known-linux-commands-part-2/
|
||||
[3]:http://www.tecmint.com/10-lesser-known-commands-for-linux-part-3/
|
||||
[4]:http://www.tecmint.com/screen-command-examples-to-manage-linux-terminals/
|
||||
[5]:http://www.tecmint.com/12-top-command-examples-in-linux/
|
||||
[6]:http://tecmint.tradepub.com/free/w_makb09/prgm.cgi
|
||||
[7]:http://www.tecmint.com/20-funny-commands-of-linux-or-linux-is-fun-in-terminal/
|
||||
Loading…
Reference in New Issue
Block a user