[root@andy ~]# whereis ls
ls: /bin/ls /usr/share/man/man1p/ls.1p.gz /usr/share/man/man1/ls.1.gz

[root@andy ~]# which cd
/usr/bin/which: no cd in (/usr/lib/qt-3.3/bin:/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin)
[root@andy ~]# where cd
-bash: where: command not found

[root@andy ~]# find / -name install.log
/root/install.log

[root@andy ~]# find /root -name "install.log*"
/root/install.log.syslog
/root/install.log

[root@andy ~]# find /root -name "*[asdf]?"
/root/anaconda-ks.cfg
/root/.viminfo
/root/japan
/root/japan/anaconda-ks.cfg

[root@andy ~]# find . -size 25k
[root@andy ~]# ll
总用量 48
-rw-------. 2 root root 1273 11月 26 05:32 anaconda-ks.cfg
-rw-r--r--. 1 root root 0 11月 26 06:05 cangls
-rw-r--r--. 1 root root 26420 11月 25 03:55 install.log
-rw-r--r--. 1 root root 7572 11月 25 03:52 install.log.syslog
drwxr-xr-x. 3 root root 4096 11月 26 05:43 japan
[root@andy ~]# find . -size +25k
./install.log
[root@andy ~]# find . -size -25k
.
./.tcshrc
./anaconda-ks.cfg
./cangls
./install.log.syslog
./.bash_profile
./.bash_logout
./.bash_history
./.bashrc
./.viminfo
./.cshrc
./japan
./japan/anaconda-ks.cfg
./japan/cangls
[root@andy ~]# find . -size -25m
find: 无效的 -size 类型“m”
[root@andy ~]# find . -size -25M
.
./.tcshrc
./anaconda-ks.cfg
./cangls
./install.log.syslog
./.bash_profile
./.bash_logout
./.bash_history
./install.log
./.bashrc
./.viminfo
./.cshrc
./japan
./japan/anaconda-ks.cfg
./japan/cangls
[root@andy ~]#

find /etc -size +20k -a -size -50k 这里的-a是与，-o是或
[root@andy ~]# find /etc -size +20k -a -size -50k
/etc/selinux/targeted/modules/active/modules/unprivuser.pp
/etc/selinux/targeted/modules/active/modules/xguest.pp
/etc/selinux/targeted/modules/active/modules/virt.pp
/etc/selinux/targeted/modules/active/modules/postfix.pp
/etc/selinux/targeted/modules/active/modules/unconfineduser.pp
/etc/selinux/targeted/modules/active/modules/nagios.pp
/etc/selinux/targeted/modules/active/modules/cups.pp
/etc/selinux/targeted/modules/active/modules/rhcs.pp
/etc/selinux/targeted/modules/active/modules/apache.pp
/etc/selinux/targeted/modules/active/modules/staff.pp
/etc/selinux/targeted/modules/active/modules/samba.pp
/etc/mime.types
/etc/sysconfig/network-scripts/network-functions-ipv6
/etc/postfix/main.cf
/etc/ld.so.cache
/etc/libreport/events/report_RHTSupportAttach.xml
/etc/libreport/events/report_RHTSupport.xml
/etc/makedev.d/01linux-2.6.x
/etc/sound/events/gnome-2.soundlist
-
find /etc -size +20k -a -size -50k -exec ls -lh {} \;
[root@andy ~]# find /etc -size +20k -a -size -50k -exec ls -lh {} \;
-rw-------. 1 root root 37K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/unprivuser.pp
-rw-------. 1 root root 26K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/xguest.pp
-rw-------. 1 root root 24K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/virt.pp
-rw-------. 1 root root 31K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/postfix.pp
-rw-------. 1 root root 29K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/unconfineduser.pp
-rw-------. 1 root root 21K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/nagios.pp
-rw-------. 1 root root 21K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/cups.pp
-rw-------. 1 root root 26K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/rhcs.pp
-rw-------. 1 root root 27K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/apache.pp
-rw-------. 1 root root 42K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/staff.pp
-rw-------. 1 root root 24K 11月 25 03:46 /etc/selinux/targeted/modules/active/modules/samba.pp
-rw-r--r--. 1 root root 43K 9月 23 2011 /etc/mime.types
-rw-r--r--. 1 root root 30K 7月 22 2014 /etc/sysconfig/network-scripts/network-functions-ipv6
-rw-r--r--. 1 root root 27K 2月 20 2014 /etc/postfix/main.cf
-rw-r--r--. 1 root root 40K 11月 25 03:52 /etc/ld.so.cache
-rw-r--r--. 1 root root 23K 10月 16 2014 /etc/libreport/events/report_RHTSupportAttach.xml
-rw-r--r--. 1 root root 22K 10月 16 2014 /etc/libreport/events/report_RHTSupport.xml
-rw-r--r--. 1 root root 28K 11月 11 2010 /etc/makedev.d/01linux-2.6.x
-rw-r--r--. 1 root root 27K 11月 12 2010 /etc/sound/events/gnome-2.soundlist

[root@andy ~]# grep "size" anaconda-ks.cfg
#part /boot --fstype=ext4 --size=200
#part swap --size=4000
#part /home --fstype=ext4 --size=2000
#part / --fstype=ext4 --grow --size=200

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title CHAR(100) NOT NULL,
author CHAR(50) NOT NULL,
description VARCHAR(255) NOT NULL,
content TEXT NOT NULL,
dateline INT(11) NOT NULL DEFAULT 0
);