tune2fs [options] device
System administration command. Tune the parameters of a Linux Second Extended Filesystem by adjusting various parameters. You
must specify the device on which the filesystem resides; it must not be mounted read/write when you change its parameters.
Specify the maximum number of mount counts between two checks on the filesystem.
Print the filename of the terminal connected to standard input.
Print help message and exit.
-s, --silent, --quiet
Print nothing to standard output, but return an exit status.
Display version information and exit.
tsort [option] [file]
Perform a topological sort on partially ordered strings in the specified file. If no file is specified or is -, read standard input. Multiple
strings on a line are separated by spaces, where each line indicates a partial ordering. The fully ordered results are written to standard
output. See the tsort info page for an example of the use of tsort for sorting lists of functions into the order they are called.
tset [options] [terminal]
reset [options] [terminal]
Initialize a terminal. The terminal to be initialized is whichever is found first from the value of terminal, the value of the TERM environment
variable, or the default terminal type. See also the reset command.
traceroute [options] host [packetsize]
TCP/IP command. Trace route taken by packets to reach network host. traceroute attempts tracing by launching UDP probe packets
with a small TTL (time-to-live), then listening for an ICMP “time exceeded” reply from a gateway. host is the destination hostname
or the IP number of the host to reach. packetsize is the packet size in bytes of the probe datagram. Default is 40 bytes.
tracepath [options] host [port]
TCP/IP command. Trace path to host and report the Maximum Transmission Unit (MTU). A simplified version of traceroute
without options meant for use by unprivileged users. If specified, it will use port to send UDP probe packets. host is the destination
hostname or the IP number of the host to reach.
tr [options] [string1 [string2]]
Translate characters. Copy standard input to standard output, substituting characters from string1 to string2, or deleting characters
cat file | tr 'A-Z' 'a-z' Change uppercase to lowercase in a file
tr ' ' '\012' < file Turn spaces into newlines (ASCII code 012):
cat file | tr -s "" "\012" > new.file Strip blank lines from file and save in new.file:
echo 'Test' | tr '[:lower:]' '[:upper:]' Case conversion
tr '\0' '\n' < /proc/$$/environ Display the startup environment for any process