如何编写一个将一个文件的内容插入另一个文件的线性脚本?

使用sed的r命令:

$ cat foo
one
two
#INSERT_HERE#
three
four
$ cat bar
foo bar
bar foo
$ sed '/#INSERT_HERE#/{ r bar
> d
> }' foo
one
two
foo bar
bar foo
three
four

cat file | while read line; do if [ "$line" = "#INSERT_HERE#" ]; then cat file_to_insert; else echo $line; fi; done

$ cat  file
one
two
#INSERT_HERE#
three
four

$ cat  file_to_insert
foo bar
bar foo

$ awk '/#INSERT_HERE#/{while((getline line<"file_to_insert")>0){ print line };next }1 ' file
one
two
foo bar
bar foo
three
four