Commands by nesses (3)

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Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Generate a shortened URL with is.gd
Check the API. You shouldn't need sed. The print-newline at the end is to prevent zsh from inserting a % after the end-of-output. Also works with http://v.gd

Print just line 4 from a textfile
Prints the 4th line and then quits. (Credit goes to flatcap in comments: http://www.commandlinefu.com/commands/view/6031/print-just-line-4-from-a-textfile#comment.)

a for loop with filling 0 format, with seq
seq allows you to format the output thanks to the -f option. This is very useful if you want to rename your files to the same format in order to be able to easily sort for example: $for i in `seq 1 3 10`; do touch foo$i ;done And $ls foo* | sort -n foo1 foo10 foo4 foo7 But: $for i in `seq -f %02g 1 3 10`; do touch foo$i ;done So $ls foo* | sort -n foo01 foo04 foo07 foo10

Deleting / Ignoring lines from the top of a file
Output lines starting at line 2.

for all who don't have the watch command
#Usage: watch timeinsecond "command"

Monitor dynamic changes in the dmesg log.
Other logs can be monitored similarly, e.g. $ watch "tail -15 /var/log/daemon.log"

Verify if ntpd is working properly
Used to verify if Network Time Protocol daemon is working properly.

check for write/read permissions
su www-apache/ftp user and then check readable: find ~/ -type d \( -wholename '/dev/*' -o -wholename '/sys/*' -o -wholename '/proc/*' \) -prune -o -exec test -r {} \; -exec echo {} readable \; 2>/dev/null check writable: find ~/ -type d \( -wholename '/dev/*' -o -wholename '/sys/*' -o -wholename '/proc/*' \) -prune -o -exec test -w {} \; -exec echo {} writable \; 2>/dev/null

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"


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