$ curl cheat.sh/
# tac
# Display and concatenate files with lines in reversed order.
# See also: `cat`.
# More information: <https://www.gnu.org/software/coreutils/tac>.

# Concatenate specific files in reversed order:
tac path/to/file1 path/to/file2 ...

# Display `stdin` in reversed order:
cat path/to/file | tac

# Use a specific [s]eparator:
tac -s separator path/to/file1 path/to/file2 ...

# Use a specific [r]egex as a [s]eparator:
tac -r -s separator path/to/file1 path/to/file2 ...

# Use a separator [b]efore each file:
tac -b path/to/file1 path/to/file2 ...

$
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