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Other Commands


alias aliasname='command' creates a temporary macro aliasname that executes command
chsh changes the shell
clear clears the screen
crontab maintain crontab files for individual users
env <VARIABLE=value> sets environmental VARIABLE to value (blank to show all)
kill pid kills process pid. kill –9 pid to force kill (use ps to list pid)
newgrp group sets group as the primary group owner for new files created
nice -n priority command executes the command with a specified priority
renice priority pid changes a program's priority level afterwards (see nice, ps).
script logs everything that you type to . “exit” to quit.
sleep time makes the computer wait for time. Try “sleep 30; echo Go”
telinit level specifies which runlevel to run at (0 = halt, 1 = single-user, 3
= full multi-user, 5 = X-windows, 6 = reboot)
umask permission
changes the default file permission for new files (ex: rw-r—r--). umask 077 makes all new files rw------. The permission
that you set is subtracted from the default 666 permission (rwrw-rw) so that umask 022 does 666 – 022 = 644 = rw-r--r--)
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