Using Cat and EOF to replace and append files in Linux

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Overwrite a file content directly or create a new file

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First of all, we're looking at a test file that doesn't exist at first.

ll/tmp/

Then perform the test

cat << EOF >/tmp/test_cat_and_eof_by_comexchan-cnblogs-com_1 test cat with EOF for file overwrite or new EOF

We are looking at the contents of the file:

Cat /tmp/test_cat_and_eof_by_comexchan-cnblogs-com_1

Execute again to see if it will overwrite

cat << EOF >/tmp/test_cat_and_eof_by_comexchan-cnblogs-com_1 test cat with EOF implementation file overwrite or new [this is the second Test] EOF

Then look at the contents of the file:

Overwrite success!

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Cat combines EOF for file append

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First add some content to test

cat << EOF >/tmp/test_cat_and_eof_by_comexchan-cnblogs-com_2 test cat with EOF implementation file append [ First add some content to test]http://comexchan.cnblogs.com/EOF

And then perform the Append

cat << EOF >>/tmp/test_cat_and_eof_by_comexchan-cnblogs-com_2 test cat with EOF implementation file append [ This is the 2nd time. Append partial text]http://comexchan.cnblogs.com/EOF

Using Cat and EOF to replace and append files in Linux