Tips & Tricks

ac -p on a BSD-System: connect time accounting

cat alert | gzip -1 - | ssh user@target cat ">" alert.odin.gz zips a file via the network

chsh change the loginshell of a user

dd if=modifyme of=modifyme.tmp ibs=4 skip=1 >/dev/null 2>&1 creates a copy of a file without the first 4 bytes

echo -e "\e[31;5m" changes the color to red and blinks. Escape sequences can be found under: http://consult.stanford.edu/pub/mail/color

fdisk -l Shows the partitions

iostat gives performance data on a solaris machine about the drives.

lsattr Show the ext2-attributes of files

lsdev Prints information about the devices!

lspci -v PCI information

lynx -head -nolist -dump http://localhost dumps a Web page into a file.

lynx http://www.raffy.ch/castle.html -dump > raffy-contents.txt

mount -t iso9660 -o loop my.iso /tmp/isomount mounts an ISO to have a look at it!

netstat -s shows you statistics on your network interfaces

netstat -lnp shows open ports and processes attachd to it.

notify %2 Notifies you when job 2 has completed.

passwd -l user Locks a user.

perl -pie 's/this/that/g' filename

pidof shows pid of a process

pgrep httpd shows all the PIDs of httpd

procinfo -f Show information about memory, irqs and processes.

ps -w shows ps with 132 columns

pwck check for inconsistencies in /etc/password

pwconv keeps /etc/shadow and /etc/passwd in synch

sa system accounting

skill Use user-name, process-name, ... to kill processes.

skill -STOP pts/2 Freeze the user on PTS/2

skill -CONT pts/2 Continue the user on PTS/2

tr -d "\015"

vipw edit the /etc/passwd, /etc/group, /etc/shadow file with the right locks

vmstat gives you virtual memory statistics

watch -d -n 60 df -k Shows, in fullscreen, every 60 seconds the output of df -k

xxd converts normal text into HEX - and vice versa