Sed和人物

Question

我正在尝试理解行代码.

这是什么意思？

   grep "^1  " file0 | grep -v MODEL | sed 's/./&E/86' | sed 's/./&  /8' | sed 's/./&  /20' > file1

Answer 1

# Add "E" after the 86th character
sed 's/./&E/86'

# Add "  " after the 8th character
sed 's/./&  /8'

# Add "  " after the 20th character
sed 's/./&  /20'

Answer 2

您可以将它们全部合并到一个表达式中,而不是grep之前使用多个管道sedsed

sed '/^1  /{/MODEL/b;s/./&E/86;s/./&  /8;s/./&  /20}' file0 > file1