cheat.sheets:cat
# POSIX way in which to cat(1); see cat(1posix).
cat -u [FILE_1 [FILE_2] ...]
# Output a file, expanding any escape sequences (default). Using this short
# one-liner let's you view the boot log how it was show at boot-time.
cat /var/log/boot.log
# This is an ever-popular useless use of cat.
cat /etc/passwd | grep '^root'
# The sane way:
grep '^root' /etc/passwd
# If in bash(1), this is often (but not always) a useless use of cat(1).
Buffer=`cat /etc/passwd`
# The sane way:
Buffer=`< /etc/passwd`
cheat:cat
# To display the contents of a file:
cat <file>
# To display file contents with line numbers
cat -n <file>
# To display file contents with line numbers (blank lines excluded)
cat -b <file>
tldr:cat
# cat
# Print and concatenate files.
# More information: <https://www.gnu.org/software/coreutils/cat>.
# Print the contents of a file to the standard output:
cat path/to/file
# Concatenate several files into an output file:
cat path/to/file1 path/to/file2 ... > path/to/output_file
# Append several files to an output file:
cat path/to/file1 path/to/file2 ... >> path/to/output_file
# Copy the contents of a file into an output file without buffering:
cat -u /dev/tty12 > /dev/tty13
# Write `stdin` to a file:
cat - > path/to/file
$
cheat.sh