Sed and vim exercises

1. Delete all whitespace characters from the beginning of lines in the/etc/grub2.conf file that begin with whitespace

[[email protected] ~]# sed-r ' s/^[[:space:]]+//g '/etc/grub2.cfg # # do don't EDIT this file## It's automatically generated by Grub2-mkconfig using templates# from/etc/grub.d and Settings from/etc/default/grub#### Begin/etc/grub.d/00_header # # #set Pager=1if [-S $prefix/grubenv]; Thenload_env ...

2. Delete all # and white space characters at the beginning of the line beginning with #, followed by at least one white-space character, in the/etc/fstab file

[[email protected] ~]# sed -r  ' [email protected]^#[[:space:]]+\[email  Protected]@g '  /etc/fstab ## /etc/fstabcreated by anaconda on wed aug   3 06:08:10 2016#Accessible filesystems, by reference, are  maintained under  '/dev/disk ' See man pages fstab (5),  findfs (8),  mount (8)  and/or blkid (8)  for more info#UUID=1aa7af5a-15a0-4cf2-a11d-8304d67c7093 /                         xfs     defaults         0 0UUID=2fb41265-5d13-4ef0-82f6-3147009bd1a5 /boot                    xfs      defaults        0 0UUID=a5a6b450-ba91-4e5b-a5ad-a17e12a2a994 /testdir                 xfs      Defaults        0 0uuid=1d6f94c4-7eb4-430c-b143-b63b498c1c98  swap                     swap    defaults        0  0

3. Add # At the beginning of each line of/root/install.log

[[Email protected] ~]# sed ' s/^/#/g '/etc/fstab

##### /etc/fstab## created by anaconda on wed aug  3  06:08:10 2016#### accessible filesystems, by reference, are maintained  under  '/dev/disk ' ## see man pages fstab (5),  findfs (8),  mount (8)   And/or blkid (8)  for more info## #UUID =1aa7af5a-15a0-4cf2-a11d-8304d67c7093 /                         xfs     defaults         0 0#UUID=2fb41265-5d13-4ef0-82f6-3147009bd1a5 /boot                    xfs      defaults        0 0#uuid=a5a6b450-ba91-4e5b-a5ad-a17e12a2a994  /testdir    &nbSp;           xfs     defaults         0 0#uuid=1d6f94c4-7eb4-430c-b143-b63b498c1c98 swap                      swap    defaults        0 0

4. Add # # At the beginning of the line in the/etc/fstab file that does not begin with #

[[email protected] ~]# sed  ' s/^[^#]/#&/g '  /etc/fstab ## /etc/fstab#  Created by anaconda on Wed Aug  3 06:08:10 2016##  accessible filesystems, by reference, are maintained under  '/dev/disk ' #  see man pages fstab (5),  findfs (8),  mount (8)  and/or blkid (8)  for  more info# #UUID =1aa7af5a-15a0-4cf2-a11d-8304d67c7093 /                        xfs      defaults        0 0#uuid= 2fb41265-5d13-4ef0-82f6-3147009bd1a5 /boot                    xfs     defaults         0 0#uuid=a5a6b450-ba91-4e5b-a5ad-a17e12a2a994 /testdir                 xfs     defaults         0 0#UUID=1d6f94c4-7eb4-430c-b143-b63b498c1c98 swap                     swap     defaults        0 0

Note: The top carriage return line does not add #, that is, there is no match return line

[[email protected] ~]# sed   '/^#/p;s/^[^#]/#&/pg;/^#/d;s/^/#/'   /etc/ Fstab ### /etc/fstab# created by anaconda on wed aug  3  06:08:10 2016## accessible filesystems, by reference, are maintained  under  '/dev/disk ' #  # see man pages fstab (5),  findfs (8),  Mount (8)  and/or blkid (8)  for more info# #UUID =1aa7af5a-15a0-4cf2-a11d-8304d67c7093  /                        xfs     defaults         0 0#UUID=2fb41265-5d13-4ef0-82f6-3147009bd1a5 /boot                    xfs      defaults        0 0#uuid=a5a6b450-ba91-4e5b-a5ad-a17e12a2a994 /testdir                 xfs      defaults        0 0#uuid= 1d6f94c4-7eb4-430c-b143-b63b498c1c98 swap                     swap    defaults         0 0

[[email protected] ~]# sed -r  ' s/^ ([^#]|$)/#&/'  /etc/fstab ### / etc/fstab# created by anaconda on wed aug  3 06:08:10 2016##  Accessible filesystems, by reference, are maintained under  '/dev/disk ' #  # see man pages fstab (5),  findfs (8),  mount (8)  and/or  Blkid (8)  for more info# #UUID =1aa7af5a-15a0-4cf2-a11d-8304d67c7093 /                         xfs     defaults        0 0# uuid=2fb41265-5d13-4ef0-82f6-3147009bd1a5 /boot                    xfs     defaults         0 0#uuid=a5a6b450-ba91-4e5b-a5ad-a17e12a2a994 /testdir                 xfs     defaults         0 0#uuid=1d6f94c4-7eb4-430c-b143-b63b498c1c98 swap                      swap    defaults        0 0

5, processing/etc/fstab path, use sed command to take out its directory name and base name

[Email protected] ~]# echo "/etc/init.d/functions" |sed ' s/.*\<//' functions

[Email protected] ~]# echo "/etc/init.d/functions" |sed-r ' [email protected][^/][email protected]@g '/etc/init.d/

[Email protected] ~]# echo "/etc/init.d/functions" |sed-r ' [email protected] (. *)/([^\]+.?) [Email protected]\[email protected] '/etc/init.d[[email protected] ~]# echo "/etc/init.d/functions" |sed-r ' [email Protected] (. *)/([^\]+.?) [Email protected]\[email protected] ' functions

6. Use SED to remove the IPv4 address of the ifconfig command

[Email protected] ~]# ifconfig |sed-r '/^[^]/!d; n;s/^ ([^]+). *\n[^0-9]+ ([0-9.] +). */\1 \2/' eno16777736:10.1.70.102lo:127.0.0.1virbr0:192.168.122.1

7. Statistics of all RPM files in the package directory on the CentOS installation CD. Number of repetitions of the second-to-last field

[[email protected] ~]# ls/mnt/packages/|sed-r ' s/.*\b ([^.] +)\. [^.] +$/\1/' |sort|uniq-c i686 2938 noarch 1 TRANS 4069 x86_64

[Email protected] ~]# ls/mnt/packages/|rev|cut-d-f2|rev|sort|uniq-c i686 2938 noarch 1 TRANS 4069 x8 6_64

1. How do I set the tab indent to 4 characters?

: Set ts=4

2. Copy the/etc/rc.d/init.d/functions file to the/tmp directory, replace the/etc/sysconfig/init in the/tmp/functions file with the/var/log

:%[email protected]/etc/sysconfig/[email Protected]/var/[email protected]

3. Delete the # number at the beginning of all lines in the/tmp/functions file that begin with # and have at least one blank character after #

:%s/^#//g

Sed and vim exercises