Commands by 6bc98f7f (6)

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Calculates the date 2 weeks ago from Saturday the specified format.
Good for automating reports that need to run from between two dates.

Extracting a range of pages from a PDF, using GhostScript
In this example we extract pages 14-17

Is it a terminal?
Oddly, the isatty(3) glibc C call doesn't have a direct analogue as a command 'isatty(1)'. All is not lost as you can use test(1). For example, your script might be run from a tty or from a GUI menu item but it needs to get user-input or give feedback. Now your script can test STDIN with 'isatty 0' or STDOUT with 'isatty 1' and use xmessage(1) if the tty is not available. The other way to test for this is with 'tty -s' - but that's only for STDIN.

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

Count lines in a file with grep
Returns the number of lines in a file, emulates "wc -l" behavior with grep.

Extract the contents of an RPM package to your current directory without installing them.
This assumes you have the 'rpm', 'rpm2cpio' and 'cpio' packages installed. This will extract the contents of the RPM package to your current directory. This is useful for working with the files that the package provides without installing the package on your system. Might be useful to create a temporary directory to hold the packages before running the extraction: $ mkdir /tmp/new-package/; cd /tmp/new-package

pipe output of a command to your clipboard
In turn you can get the contents of your clipboard by typing xsel by itself with no arguments: $ xsel This command requires you to install the xsel utility which is free

Determine status of a RAID write-intent bitmap
Report information about a bitmap file.

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"

Unzip multi-part zip archive
Assuming you have a multi-part archive like "archive.zip archive.z01 archive.z02 ...", unzip will not handle these correctly. If you "fix" the parts into one big file with zip -F before, it works.


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