覚え書き 未分類の覚え書き。 dd コマンドについて ピンポイント書き込み 例えば、64 バイトのデータの 31-32 バイト目だけを書き換えたい場合。 # od -Ad -tx1 test -v 0000000 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0000016 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0000032 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0000048 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0000064 # echo -n $'\x55'$'\xaa' | dd of=test bs=1 seek=30 conv=notrunc 2+0 r