经常使用Linux命令

This is a linux command line reference for common operations.

Examples marked with ? are valid/safe to paste without modification into a terminal, so you may want to keep a terminal window open while reading this so you can cut & paste.
All these commands have been tested both on Fedora and Ubuntu.

个人实践环境：redhat-release-5Server-5.4。

apropos whatis	Show commands pertinent to string. See alsothreadsafe
man -t man | ps2pdf -> man.pdf	make a pdf of a manual page
which command	Show full path name of command
time command	See how long a command takes
time cat	Start stopwatch. Ctrl-d to stop. See also sw
nice info	Run a low priority command (The “info” reader in this case)
renice 19 -p $$	Make shell (script) low priority. Use for non interactive tasks

man -t man | ps2pdf -> man.pdf 默认用不了。 到http://www.ghostscript.com/download/gsdnld.html下载ghostscript，当前最新版本时9.0.4。

配置的时候，告知须要更高版本的glibc。

升级一下glibc吧，到ftp://ftp.gnu.org/gnu/glibc/下载。配置的时候又报：

configure: error: gcc must provide the <cpuid.h> header

 
一查，原来又要升级GCC，https://bugs.gentoo.org/292174?id=292174。

耐着性子去http://gcc.gnu.org/，又Download最新的GCC4.6.1，配置时又报一堆依赖的东东。

想一想何须呢，为了这么个ghostscript费这么大周折，找个低版本的试试吧。因而下载了ghostscript-9.02，配置，编译，安装，一切都很顺利。

再来运行 man -t man | ps2pdf -&gt; man.pdf，这回就OK了。

看看pdf效果。

which command 也是极其有用的一个命令。 

公司的云平台不少东西都是预先设好的，起初我连java安装在哪里都不知道，找了半天。有了找个命令，一下搞定。

目录导航 dir navigation

cd -	Go to previous directory
cd	Go to $HOME directory
(cd dir && command)	Go to dir, execute command and return to current dir
pushd .	Put current dir on stack so you can popd back to it

 

文件查找 file searching

alias l='ls -l -color=auto'	quick dir listing
ls -lrt	List files by date. See also newest andfind_mm_yyyy
ls /usr/bin | pr -T9 -W$COLUMNS	Print in 9 columns to width of terminal
find -name '*.[ch]' | xargs grep -E 'expr'	Search ‘expr’ in this dir and below. See alsofindrepo
find -type f -print0 | xargs -r0 grep -F 'example'	Search all regular files for ‘example’ in this dir and below
find -maxdepth 1 -type f | xargs grep -F 'example'	Search all regular files for ‘example’ in this dir
find -maxdepth 1 -type d | while read dir; do echo $dir; echo cmd2; done	Process each item with multiple commands (in while loop)
find -type f ! -perm -444	Find files not readable by all (useful for website)
find -type d ! -perm -111	Find dirs not accessible by all (useful for web site)
locate -r 'file[^/]*.txt'	Search cached index for names. This re is like glob *file*.txt
look reference	Quickly search (sorted) dictionary for prefix
grep -color reference /usr/share/dict/words	Highlight occurances of regular expression in dictionary

alias l='ls -l -color=auto' 在RHEL下应为 alias l='ls -l --color=auto'。原文中有不少这样的错误，两个“-”，变成了一个长的“—”估计做者也是在Windows下写的。

归档压缩 archives and compression

gpg -c file	Encrypt file
gpg file.gpg	Decrypt file
tar -c dir/ | bzip2 > dir.tar.bz2	Make compressed archive of dir/
bzip2 -dc dir.tar.bz2 | tar -x	Extract archive (use gzip instead of bzip2 for tar.gz files)
tar -c dir/ | gzip | gpg -c | ssh user@remote 'dd of=dir.tar.gz.gpg'	Make encrypted archive of dir/ on remote machine
find dir/ -name '*.txt' | tar -c --files-from=- | bzip2 > dir_txt.tar.bz2	Make archive of subset of dir/ and below
find dir/ -name '*.txt' | xargs cp -a --target-directory=dir_txt/ --parents	Make copy of subset of dir/ and below
( tar -c /dir/to/copy ) | ( cd /where/to/ && tar -x -p )	Copy (with permissions) copy/ dir to /where/to/ dir
( cd /dir/to/copy && tar -c . ) | ( cd /where/to/ && tar -x -p )	Copy (with permissions) contents of copy/ dir to /where/to/
( tar -c /dir/to/copy ) | ssh -C user@remote cd /where/to/ && tar -x -p	Copy (with permissions) copy/ dir to remote:/where/to/ dir
dd bs=1M if=/dev/sda | gzip | ssh user@remote 'dd of=sda.gz'	Backup harddisk to remote machine

试试加密解密，就加密刚刚建立的man.pdf吧。

 

重复输入passphrase。

完后查看，会在当前目录生成一个.gpg文件。

再来试着解密，输入刚才的passphrase。

tar -c dir/ | gzip | gpg -c | ssh user@remote 'dd of=dir.tar.gz.gpg' 感受不是很实用，加密时会让你输入passphrase，ssh登陆也须要输入用户密码，重叠到一块儿，容易弄错。

rsync (Network efficient file copier: Use the –dry-run option for testing)

rsync -P rsync://rsync.server.com/path/to/file file	Only get diffs. Do multiple times for troublesome downloads
rsync –bwlimit=1000 fromfile tofile	Locally copy with rate limit. It’s like nice for I/O
rsync -az -e ssh –delete ~/public_html/ remote.com:’~/public_html’	Mirror web site (using compression and encryption)
rsync -auz -e ssh remote:/dir/ . && rsync -auz -e ssh .remote:/dir/	Synchronize current directory with remote one

上面的命令默认连远程用户的root 用户，换成同事的帐号试了试。

rsync -P user@remote:/home/user/sync/hadoop-0.21.0.tar.gz test-hadoop.tar.gz

rsync --bwlimit=1000 hadoop-0.21.0.tar.gz local-hadoop-0.21.0.tar.gz

设成1000，速度还真是慢，现学现用了一把 time。

time rsync --bwlimit=1000000000 hadoop-0.21.0.tar.gz local-hadoop-0.21.0.tar.gz

rsync -az -e ssh --delete hadoop-0.21.0.tar.gz user@remote:'/home/user/sync/hadoop-0.21.0.tar.gz'

没大弄明白这条命令到底作什么用。

第四条命令，搞不懂后面的 && rsync -auz -e ssh .remote:/dir/ 是干吗的，下面这条就能够同步远程目录到当前目录。

rsync -auz -e ssh user@remote:/home/user/sync/ .

ssh (Secure SHell)

ssh $USER@$HOST command	Run command on $HOST as $USER (default command=shell)
ssh -f -Y $USER@$HOSTNAME xeyes	Run GUI command on $HOSTNAME as $USER
scp -p -r $USER@$HOST: file dir/	Copy with permissions to $USER’s home directory on $HOST
ssh -g -L 8080:localhost:80 root@$HOST	Forward connections to $HOSTNAME:8080 out to $HOST:80
ssh -R 1434:imap:143 root@$HOST	Forward connections from $HOST:1434 in to imap:143

ssh 属于常见命令，再也不啰嗦，提一下xeyes，能够参见 http://en.wikipedia.org/wiki/Xeyes。

wget (multi purpose download tool)

(cd dir/ && wget -nd -pHEKkhttp://www.joinebook.com/cmdline.html)	Store local browsable version of a page to the current dir
wget -c http://www.example.com/large.file	Continue downloading a partially downloaded file
wget -r -nd -np -l1 -A '*.jpg' http://www.example.com/	Download a set of files to the current directory
wget ftp://remote/file[1-9].iso/	FTP supports globbing directly
wget -q -O- http://www.joinebook.com/linux-command.html | grep 'a href' | head	Process output directly
echo 'wget url' | at 01:00	Download url at 1AM to current dir
wget –limit-rate=20k url	Do a low priority download (limit to 20KB/s in this case)
wget -nv –spider –force-html -i bookmarks.html	Check links in a file
wget –mirror http://www.example.com/	Efficiently update a local copy of a site (handy from cron)

第一条命令的连接已经失效，另外-pHEKk后还须要一个空格和URL分开。

wget -nd -pHEKk http://www.joinebook.com/linux-command.html

中断下载测试，下载QQ Linux 版玩玩吧，wget http://3.duote.org/qq2011beta3.zip

中断再继续，wget -c http://3.duote.org/qq2011beta3.zip

echo 'wget http://www.joinebook.com/linux-command.html' | at 01:00

networking (Note ifconfig, route, mii-tool, nslookup commands are obsolete)

ethtool eth0	Show status of ethernet interface eth0
ethtool --change eth0 autoneg off speed 100 duplex full	Manually set ethernet interface speed
iwconfig eth1	Show status of wireless interface eth1
iwconfig eth1 rate 1Mb/s fixed	Manually set wireless interface speed
iwlist scan	List wireless networks in range
ip link show	List network interfaces
ip link set dev eth0 name wan	Rename interface eth0 to wan
ip link set dev eth0 up	Bring interface eth0 up (or down)
ip addr show	List addresses for interfaces
ip addr add 1.2.3.4/24 brd + dev eth0	Add (or del) ip and mask (255.255.255.0)
ip route show	List routing table
ip route add default via 1.2.3.254	Set default gateway to 1.2.3.254
tc qdisc add dev lo root handle 1:0 netem delay 20msec	Add 20ms latency to loopback device (for testing)
tc qdisc del dev lo root	Remove latency added above
host boykma.pro	Lookup DNS ip address for name or vice versa
hostname -i	Lookup local ip address (equivalent to host `hostname`)
whois joinebook.com	Lookup whois info for hostname or ip address
netstat -tupl	List internet services on a system
netstat -tup	List active connections to/from system

转到这里，已然有些倦了，留待下次完成剩余部分。

原文地址：http://www.joinebook.com/linux-command.html。