$ egrep "^COMP[29]041" enrolments | grep "|F$" | wc -l
24
$ egrep "^COMP[29]041" enrolments | egrep "|F$" | wc -l
166
$
文件enrolments
的内容下半年egrep命令:为什么我得到不同的答案,当我改变的grep在每个
COMP2041|4836917|Ruld, Ruld |3978/2|M
COMP2041|4850109|Rvyiparzal, Ilbvuy |3979/3|M
COMP2041|2858836|Rzild, Fia Held |3730/4|M
COMP2041|4823158|Sheld, Yild |3978/2|M
COMP2041|4818044|Sheo, Sheo |3978/2|M
COMP2041|4818497|Sheo, Xa |3978/2|M
COMP9041|4899688|Shild, Ge |8680/2|M
COMP2041|4869506|Shild, Yild |3645/2|M
COMP9041|4897426|Shild, Yild |8680/2|M
COMP9041|4368551|Sho, Wuld |8684 |M
COMP2041|4339940|Shuld, Puaxail Baili |3978/3|F
COMP2041|4330093|Veh, Yeold-He |3711/3|M
COMP2041|2230267|Vikil, Ivrha |3978/3|F
COMP2041|4312663|Viy Chiobhova, Jiozrigh |3978/1|M
.......
的问题是,为什么我得到不同的答案时,我改变了grep
到egrep
在每个后半部分。 grep
和egrep
有什么区别?
这个问题的'有什么不同'部分相当于Unix SE问题;示例材料完全不在场外副本中。 –