Set field separator char from command line. Prints first, second and lsat columns. Show Sample Output
remove all carriage return of a given file (or input, if used with | ) and replace them with a space (or whatever character is after %s) Show Sample Output
% lsof -v lsof version information: revision: 4.78
Same as 7272 but that one was too dangerous so i added -P to prompt users to continue or cancel Note the double space: "...^ii␣␣linux-image-2..." Like 5813, but fixes two bugs: [1]This leaves the meta-packages 'linux-headers-generic' and 'linux-image-generic' alone so that automatic upgrades work correctly in the future. [2]Kernels newer than the currently running one are left alone (this can happen if you didn't reboot after installing a new kernel).
Outputs the real time it takes a Redis ping to run in thousands of a second without any proceeding 0's. Useful for logging or scripted action.
If you do not have shuf or an -R option in sort, you can fall back on awk. This provides maximum portability IMO. The command first collects words from the dictionary that match the criteria - in this case: lower case words with no punctuation that are 4 to 8 characters long. It then prints 4 random entries. I decided to print each word on a separate line to improve readability.
like #9295, but awkish instead of perlish
Git uses secure hash sums for its revision numbers. I'm sure this is fine and dandy for ultra-secure computing, but it's less than optimal for humans. Thus, this will give you sequential revision numbers in Git all the way from the first commit.
On wired connections set 'eth0' instead of 'wlan0'
display IP's that unsuccessfully attempted to login 5 or more times today may want to filter any trusted IP's and the localhost useful for obtaining a list IP addresses to block on the firewall Show Sample Output
Useful to check DDoS attacks on servers. Show Sample Output
grep's -c outputs how may matches there are for a given file as "file:N", cut takes the N's and awk does the sum. Show Sample Output
Removes trailing newline; colon becomes record separator and newline becomes field separator, only the first field is ever printed. Replaces empty entries with $PWD. Also prepend relative directories (like ".") with the current directory ($PWD). Can change PWD with env(1) to get tricky in (non-Bourne) scripts. Show Sample Output
I have a directory containing log files. This command delete all but the 5 latest logs. Here is how it works: * The ls -t command list all files with the latest ones at the top * The awk's expression means: for those lines greater than 5, delete.
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.
Although Exim will purge frozen (undeliverable) messages over time, the command "exim -Mrm #id#" where #id# is a particular message ID will purge a message immediately. Being lazy, I don't want to type the command for each frozen message, so I wrote the one-liner to do it for me.
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