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There's no need for ls or grep; printf is builtin to most modern shells
no need to use grep.
It's not a big line, and it *may not* work for everybody, I guess it depends on the detail of access_log configuration in your httpd.conf. I use it as a prerotate command for logrotate in httpd section so it executes before access_log rotation, everyday at midnight.
Extracts the model name of the CPU and displays it on screen.
Sometimes, you don't really care about all the other information that ifconfig spits at you (however useful it may otherwise be). You just want an IP. This strips out all the crap and gives you exactly what you want.
If you issue the "set" command, you'll see a list of variables and functions. This command displays just those functions' names.
Really useful way to combine less and grep while browsing log files.
I can't figure out how to make it into a true oneliner so paste it into a script file called lgrep:
lgrep searchfor file1 [file2 file3]
Advanced example (grep for an Exception in logfiles that starts with qc):
lgrep Exception $(find . -name "qc*.log")
Place this in your .bash_profile and you can use it two different ways. If you issue 'h' on its own, then it acts like the history command. If you issue:
Then it will display all the history with the word 'cd'
I needed a way to search all files in a web directory that contained a certain string, and replace that string with another string. In the example, I am searching for "askapache" and replacing that string with "htaccess". I wanted this to happen as a cron job, and it was important that this happened as fast as possible while at the same time not hogging the CPU since the machine is a server.
So this script uses the nice command to run the sh shell with the command, which makes the whole thing run with priority 19, meaning it won't hog CPU processing. And the -P5 option to the xargs command means it will run 5 separate grep and sed processes simultaneously, so this is much much faster than running a single grep or sed. You may want to do -P0 which is unlimited if you aren't worried about too many processes or if you don't have to deal with process killers in the bg.
Also, the -m1 command to grep means stop grepping this file for matches after the first match, which also saves time.
This is how I typically grep. -R recurse into subdirectories, -n show line numbers of matches, -i ignore case, -s suppress "doesn't exist" and "can't read" messages, -I ignore binary files (technically, process them as having no matches, important for showing inverted results with -v)
I have grep aliased to "grep --color=auto" as well, but that's a matter of formatting not function.
After executing this, click on a window you want to track X Window events in.
Explaination: "xev will track events in the window with the following -id, which we get by greping window information obtained by xwininfo"
for one line per process:
ss -p | cat
for established sockets only:
ss -p | grep STA
for just process names:
ss -p | cut -f2 -sd\"
ss -p | grep STA | cut -f2 -d\"
show only the name of the apps that are using internet
Show apps that use internet connection at the moment.
Can be used to discover what programms create internet traffic. Skip the part after awk to get more details, though it will not work showing only unique processes.
This version will work with other languages such as Spanish and Portuguese, if the word for "ESTABLISHED" still contain the fragment "STAB"(e.g. "ESTABELECIDO")
This corrects duplicate output from the previous command.
Can be used to discover what programms create internet traffic. Skip the part after awk to get more details.
Has anyone an idea why the uniq doesn't work propperly here (see sample output)?
Handles everything except octets with 255. Ran through ip generator with variable octet lengths.
This obey that you don't match any broadcast or network addresses and stay between 18.104.22.168 - 254.254.254.254
regex to match an ip
Make sure that find does not touch anything other than regular files, and handles non-standard characters in filenames while passing to xargs.