fgrep(fixed regexp)
fgrep(fixed regexp)功能说明：查找文件里符合条件的字符串。
语 法：fgrep [范本样式][文件或目录...]
补充说明：本指令相当于执行grep指令加上参数"-F"，详见grep指令说明。
fgrep
fgrep [options] string [files]
Search one or more files for lines that match the specified text string. Exit status is 0 if any lines match, 1 if not, and 2 for errors. fgrep is faster than normal grep searches, but less flexible: it can only find fixed text, not regular expressions.
See grep for the list of available options. Also see egrep.
Examples
Print lines in file that don't contain any spaces:
fgrep -v ' ' file
Print lines in file that contain the words in the file spell_list:
fgrep -f spell_list file