一、find查找用法
find [-H] [-L] [-P] [-Olevel] [-D help|tree|search|stat|rates|opt|exec] [path...] [expression]
find默认的寻找路径为当前目录，并且默认的表达式为-print
１、列出某个路径下所有文件，包括子目录。
find /data -name “*”
２、查找在某个路径下所有包含“test abc”字符串的文件
find /data -name “*” | xargs grep “test abc”
3、-name:按照文件名查找
find /data -name “*.txt”
４、-perm:按照权限查找文件
find /data -perm 755 查找权限为755的文件
５、-user和－nouser
find /data -user zhao -print 查找文件属主是zhao的文件
find /data -nouser -print 查找文件属主已经被删除的文件
6、-group和－nogroup
find /data -group test -print 查找文件群组是zhao的文件
7、按照时间
find /data -mtime -5 -print 文件更改时间在5天内的文件
find /data -mtime +3 -print 文件更改时间在3天前的文件
find /data -newer file1 -print 查找比文件file1新的文件
8、按照类型查找
find /data -type d -print 查找所有目录
9、按照大小
find /data -size +1000000C -print 查找文件大小大于1000000字节(1M)的文件
10、查找位于本文件系统里面的文件
find /data -name “*.txt” -mount -print
-exec,-ok:find命令对于匹配文件执行该参数所给出shell命令，相应命令形式为: ‘command’ {} \;
-ok 在执行命令前要确认
find /data -type f -exec ls -l {} \;
find /data -name “*.log” -mtime +5 -ok rm {} \;
find /data -name core -exec rm {} \;
使用-x dev参数
防止find搜索其他分区
find . -size 0 -exec rm {} \;
删除尺寸为０的文件
11. xargs与-exec功能类似
find /data -type f |xargs grep -i “Mary”
在所有文件中检索字符串Mary
ls *~ |xargs rm -rf 删除所有以~结尾的文件
二、grep用法
Usage: grep [OPTION]... PATTERN [FILE]..
Regexp selection and interpretation:
-E, --extended-regexp PATTERN is an extended regular expression (ERE)
-F, --fixed-strings PATTERN is a set of newline-separated fixed strings
-G, --basic-regexp PATTERN is a basic regular expression (BRE)
-P, --perl-regexp PATTERN is a Perl regular expression
-e, --regexp=PATTERN use PATTERN for matching
-f, --file=FILE obtain PATTERN from FILE
-i, --ignore-case ignore case distinctions
-w, --word-regexp force PATTERN to match only whole words
-x, --line-regexp force PATTERN to match only whole lines
-z, --null-data a data line ends in 0 byte, not newline
Miscellaneous:
-s, --no-messages suppress error messages
-v, --invert-match select non-matching lines
-V, --version print version information and exit
--help display this help and exit
--mmap ignored for backwards compatibility
Output control:
-m, --max-count=NUM stop after NUM matches
-b, --byte-offset print the byte offset with output lines
-n, --line-number print line number with output lines
--line-buffered flush output on every line
-H, --with-filename print the filename for each match
-h, --no-filename suppress the prefixing filename on output
--label=LABEL print LABEL as filename for standard input
-o, --only-matching show only the part of a line matching PATTERN
-q, --quiet, --silent suppress all normal output
--binary-files=TYPE assume that binary files are TYPE;
TYPE is `binary', `text', or `without-match'
-a, --text equivalent to --binary-files=text
-I equivalent to --binary-files=without-match
-d, --directories=ACTION how to handle directories;
ACTION is `read', `recurse', or `skip'
-D, --devices=ACTION how to handle devices, FIFOs and sockets;
ACTION is `read' or `skip'
-R, -r, --recursive equivalent to --directories=recurse
--include=FILE_PATTERN search only files that match FILE_PATTERN
--exclude=FILE_PATTERN skip files and directories matching FILE_PATTERN
--exclude-from=FILE skip files matching any file pattern from FILE
--exclude-dir=PATTERN directories that match PATTERN will be skipped.
-L, --files-without-match print only names of FILEs containing no match
-l, --files-with-matches print only names of FILEs containing matches
-c, --count print only a count of matching lines per FILE
-T, --initial-tab make tabs line up (if needed)
-Z, --null print 0 byte after FILE name
grep与正则表达式同用
grep “^[^abc]” *.f 提取行首不是abc的行
grep “[0-9]\{3\}[8]” *.f 提取类似xxx8的行，x表示任意数字
grep “a\{2\}” *.f 显示a至少出现两次的行，注意grep是以行处理单位的
grep -n “^$” file 列出空行的行号
-E参数，可以使用”与”和”或”模式
grep -E “abc | def” *.f 显示包含abc或者def的行
ex:
ls -l | grep “^$” 显示目录
ls -l | grep “^d” 显示文件
ls -l | grep “^d..x..x..x” 显示特定权限的目录