configファイル修正したり、ソースをいじった際によくdiffコマンドを使って変更点を確認しますよね。
オプション無しで実行すると見にくいけど、あるオプションを付けてやると
gitっぽく出力してくれたり、WinMergeっぽく出力してくれるようになります。
覚えておくと便利なので、ぜひ見ていってください。
オプション無し
オプション無しでdiff を叩くと以下のように出力されます。
見にくい・・
慣れない人が見るとなんじゃこりゃとなりそうですね。
[root@bacchi ~]# diff /etc/ntp.conf.orig /etc/ntp.conf
8,9c8,10
< restrict default kod nomodify notrap nopeer noquery
restrict default ignore
> restrict -6 default ignore
> restrict ntp1.sakura.ad.jp kod nomodify notrap nopeer noquery
22,24c23
< server 0.centos.pool.ntp.org
< server 1.centos.pool.ntp.org
server ntp1.sakura.ad.jp
-u オプション
-u オプションをつけると見やすくなります。
エンジニアな人なら見慣れた形式ですが、エンジニアじゃない人にとってはまだとっつきにくいかな。
[root@bacchi ~]# diff -u /etc/ntp.conf.orig /etc/ntp.conf
--- /etc/ntp.conf.orig 2009-07-22 14:37:01.000000000 +0900
+++ /etc/ntp.conf 2012-09-17 20:55:27.571717816 +0900
@@ -5,8 +5,9 @@
# Permit time synchronization with our time source, but do not
# permit the source to query or modify the service on this system.
-restrict default kod nomodify notrap nopeer noquery
-restrict -6 default kod nomodify notrap nopeer noquery
+restrict default ignore
+restrict -6 default ignore
+restrict ntp1.sakura.ad.jp kod nomodify notrap nopeer noquery
# Permit all access over the loopback interface. This could
# be tightened as well, but to do so would effect some of
@@ -19,9 +20,7 @@
# Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/join.html).
-server 0.centos.pool.ntp.org
-server 1.centos.pool.ntp.org
-server 2.centos.pool.ntp.org
+server ntp1.sakura.ad.jp
#broadcast 192.168.1.255 autokey # broadcast server
#broadcastclient # broadcast client
-ybBw オプション
一番のオススメの-ybBw オプション。
ファイルを左右に出力して、変更を|、追加削除をで表します。
WinMergeっぽく出力してくれるのでわかりやすい！
難点は小さい画面だととたんにダメな子になること。
[root@bacchi ~]# diff -ybBw /etc/ntp.conf.orig /etc/ntp.conf
# For more information about this file, see the man pages # For more information about this file, see the man pages
# ntp.conf(5), ntp_acc(5), ntp_auth(5), ntp_clock(5), ntp_mis # ntp.conf(5), ntp_acc(5), ntp_auth(5), ntp_clock(5), ntp_mis
driftfile /var/lib/ntp/drift driftfile /var/lib/ntp/drift
# Permit time synchronization with our time source, but do no # Permit time synchronization with our time source, but do no
# permit the source to query or modify the service on this sy # permit the source to query or modify the service on this sy
restrict default kod nomodify notrap nopeer noquery | restrict default ignore
restrict -6 default kod nomodify notrap nopeer noquery | restrict -6 default ignore
> restrict ntp1.sakura.ad.jp kod nomodify notrap nopeer noquery
# Permit all access over the loopback interface. This could # Permit all access over the loopback interface. This could
# be tightened as well, but to do so would effect some of # be tightened as well, but to do so would effect some of
# the administrative functions. # the administrative functions.
restrict 127.0.0.1 restrict 127.0.0.1
restrict -6 ::1 restrict -6 ::1
# Hosts on local network are less restricted. # Hosts on local network are less restricted.
#restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap #restrict 192.168.1.0 mask 255.255.255.0 nomodify notrap
# Use public servers from the pool.ntp.org project. # Use public servers from the pool.ntp.org project.
# Please consider joining the pool (http://www.pool.ntp.org/j # Please consider joining the pool (http://www.pool.ntp.org/j
server 0.centos.pool.ntp.org | server ntp1.sakura.ad.jp
server 1.centos.pool.ntp.org <
server 2.centos.pool.ntp.org <