使用xargs和xargs -0的Bash命令

Question

I just found difference between two commands:

echo sum.txt| xargs cat

This will output content of sum.txt

echo sum.txt| xargs -0 cat

This shows error:

cat: sum.txt
: No such file or directory

I know -0 will treat null bytes as delimiter. And i think the new line starts with : is because echo command produce new lines. And doesn't produce output like:

cat: sum.txt: No such file or directory

But if echo produce new lines why the first command can succeed? since xargs use white spaces as delimiter by default.

Answer 1

I think what is happening will become more clear if you replace cat with echo -n as an experiment.

echo sum.txt| xargs  echo -n
echo sum.txt | xargs -0 echo -n

In the first example, xargs breaks on the newline and discards the newline , leaving just sum.txt .

In the second example, xargs breaks on the end of the EOF at the end of the output of the first echo , resulting in the string 'sum.txt\\n' .