Commands tagged awk (348)

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watch snapshots commit in VMware ESX
To monitor .vmdk files during snapshot deletion (commit) on ESX only (ESXi doesn't have the watch command): 1. Navigate to the VM directory containing .vmdk files. # watch "ls -tough --full-time *.vmdk" where: -t sorts by modification time -o do not list group information (to narrow the output) -u sorts by access time -g only here for the purpose to easily remember the created mnemonic word 'tough' -h prints sizes in human readable format (e.g., 1K 234M 2G) --full-time sets the time style to full-iso and does not list user information (to narrow the output) optionally useful parameters to the watch command: -d highlight changes between updates -n seconds to wait between updates (default is 2) -t turn off printing the header

Grab IP address on machine with multiple interfaces
Instead of hard-coding in a check to scrape info from ifconfig based on a specific interface, do it in a more portable way. This works really well if you switch between wired, wireless, bluetooth or even VPN connections. You can get your current IP in a script (since it'll be something like tun0 instead of eth0 or wlan1). This uses a well known public ip address 8.8.8.8, but it doesn't actually connect to it, it just shows you the route it would take.

List just the executable files (or directories) in current directory
Does an 'ls' on just the files and directories in the current directory with an execute bit turned on. This version will list directories. Just tack on "-type f" to the start of the find to omit listing directories and list only files.

Debug redirects between production reloads
Watches the headers of a curl, following any redirects and printing only the HTTP status and the location of the possible redirects.

In place line numbering
Add permanent line numbers to a file without creating a temp file. The rm command deletes file10 while the nl command works on the open file descriptor of file10 which it outputs into a new file again named file10. The new file10 will now be numbered in the same directory with the same file name and content as before, but it will in fact be a new file, using (ls -i) to show its inode number will prove this.

Detect illegal access to kernel space, potentially useful for Meltdown detection
Based on capsule8 agent examples, not rigorously tested

Display condensed log of changes to current git repository
Assuming you are working within a git repository, you can run the above command & see what has changed in reverse chronological order, with one commit per line. Other formatting variations to 'oneline' include 'short', 'medium', 'full', 'fuller', 'email' or 'raw'.

Create a backup of the file.
It will create a backup of the filename. The advantage is that if you list the folder the backups will be sorted by date. The command works on any unix in bash.

print shared library dependencies
May be used on (embedded) systems lack ldd

Shrink more than one blank lines to one in VIM.


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