Commands tagged net (9)

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Printout a list of field numbers (awk index) from a CSV file with headers as first line.
Useful to identify the field number in big CSV files with large number of fields. The index is the reference to use in processing with commands like 'cut' or 'awk' involved.

Dump and bz2compress a mysql db
To also move the db backup to another location you could pass the output to the dd command instead of a file $mysqldump -u user -h host -ppwd -B dbname | bzip2 -zc9 | dd ssh [email protected] "dd of=db_dump"

Rip audio from a video file.
Replace and accordingly.

File rotation without rename command
Rotates log files with "gz"-extension in a directory for 7 days and enumerates the number in file name. i.e.: logfile.1.gz > logfile.2.gz I needed this line due to the limitations on AIX Unix systems which do not ship with the rename command.

Clone perms and owner group from one file to another
Copy both perms and owner group from one file to another.

cd to (or operate on) a file across parallel directories
This is useful for quickly jumping around branches in a file system, or operating on a parellel file. This is tested in bash. cd to (substitute in PWD, a for b) where PWD is the bash environmental variable for the "working directory"

Convert JSON to YAML
Requires installing json2yaml via npm: npm install -g json2yaml (can also pipe from stdin) Ref: https://www.npmjs.com/package/json2yaml

Lines per second in a log file

list all opened ports on host
in loop, until the last port (65535), list all opened ports on host. in the sample I used localhost, but you can replace with any host to test.

The Chronic: run a command every N seconds in the background
Chronic Bash function: $ chronic 3600 time # Print the time in your shell every hour $ chronic 60 updatedb > /dev/null # update slocate every minute Note: use 'jobs' to list background tasks and fg/bg to take control of them.


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