Insert a line at the top of a text file without sed or awk or bash loops

tac myfile.txt > /tmp/temp; echo "my line" >> /tmp/temp; tac /tmp/temp > myfile.txt
Yet another way to add a line at the top a of text file with the help of the tac command (reverse cat).

By: thargos
2018-10-17 16:16:49

1 Alternatives + Submit Alt

What Others Think

Can also be done without tac: cat /tmp/temp; mv /tmp/temp myfile.txt Alternatively: { echo "my line"; cat myfile.txt; } > /tmp/temp; mv /tmp/temp myfile.txt
RazZziel · 139 weeks and 4 days ago

What do you think?

Any thoughts on this command? Does it work on your machine? Can you do the same thing with only 14 characters?

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