alias ifconfig='/sbin/ifconfig && echo `/sbin/ifconfig | sed -n 2p | awk "{ print \\$2 }" | grep -o "[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}\.[0-9]\{1,3\}"` | xclip -selection clipboard'

或者

xclip -sel clip < file 

此时你就可以在网页等编辑框CTRL+V了。

项目主页：http://sourceforge.net/projects/xclip/
命令man page: http://linux.die.net/man/1/xclip

-i, -in

read text into X selection from standard input or files (default)

-o, -out

prints the selection to standard out (generally for piping to a file or program)

-f, -filter

when xclip is invoked in the in mode with output level set to silent (the defaults), the filter option will cause xclip to print the text piped to standard in back to standard out unmodified

-l, -loops

number of X selection requests (pastes into X applications) to wait for before exiting, with a value of 0 (default) causing xclip to wait for an unlimited number of requests until another application (possibly another invocation of xclip) takes ownership of the selection

-d, -display

X display to use (e.g. "localhost:0"), xclip defaults to the value in $DISPLAY if this option is omitted

使用xsel命令。

示例：

cat README.TXT | xsel
cat README.TXT | xsel -b # 如有问题可以试试-b选项
xsel < README.TXT
# 将readme.txt的文本放入剪贴板xsel -c
# 清空剪贴板

4. Mac下

使用pbcopy命令。 # 对应有个pbpaste命令。

示例：

echo 'Hello World!' | pbcopy
# 将字符串Hello World放入剪贴板

cat myFile.txt | pbcopy

pbpaste > file.txt

命令的结果输出时，如果给复制命令（即上面提到的命令clip、xsel、pbcopy）那么命令输出就看不到了。如果你想先看到命令的输出，可以下面这么做。

$ echo 'Hello World!' | tee tmp.file.txt
Hello World!
$ xsel < tmp.file.txt
$ rm tmp.file.txt

使用下面的命令：

$ pbcopy < ~/.ssh/id_rsa.pub