shell 技巧

[[email protected] scripts]$ a="abc|def|ghi"
[[email protected] scripts]$ echo ${a%|*}
abc|def
[[email protected] scripts]$ echo ${a%%|*}
abc
[[email protected] scripts]$ echo ${a##|*}
abc|def|ghi
[[email protected] scripts]$ man bash
[[email protected] scripts]$ echo ${a##|*}
abc|def|ghi
[[email protected] scripts]$ echo ${a##|*}
abc|def|ghi
[[email protected] scripts]$ echo ${a##*|}
ghi
[[email protected] scripts]$ echo ${a#*|}
def|ghi