unix - how to append to an existing line using sed

Question

I would like to output a file's contents appended with a string without creating a new line.

so far my command places the appended string on a new line:

sed -e 'a foo' file.txt
>> file contents...
>> foo

I want the output to look like this:

>> file contents...foo

Answer 1

使用sed（在Archlinux&上成功测试Minix）：

sed '$s/$/foo/' file.txt

$开头，意思是文件的结尾。

如果您需要在每行添加foo ：

sed 's/$/foo/' file.txt

在最新的上下文中，$平均行尾