将命令结果赋值给一个变量

#!/bin/basha=23              # Simple caseecho $ab=$aecho $becho# Now, getting a little bit fancier (command substitution).a=`echo Hello!`   # Assigns result of 'echo' command to 'a' ...echo $a#  Note that including an exclamation mark (!) within a#+ command substitution construct will not work from the command-line,#+ since this triggers the Bash "history mechanism."#  Inside a script, however, the history functions are disabled.a=`ls -l /home`         # Assigns result of 'ls -l' command to 'a'echo $a           # Unquoted, however, it removes tabs and newlines.echoecho "$a"         # The quoted variable preserves whitespace.                  # (See the chapter on "Quoting.")exit 0

结果：

23
23

Hello!
total 8 drwxrwxrwx 15 root root 4096 2012-10-27 10:47 code drwxr-xr-x 4 user user 4096 2012-10-24 12:58 user

total 8
drwxrwxrwx 15 root root 4096 2012-10-27 10:47 code
drwxr-xr-x  4 user user 4096 2012-10-24 12:58 user