Commands by servermanaged (56)

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Fix time-stamped filenames of JPEG images according to the EXIF date the photo was taken
For each *.jpg or *.JPG file in the current directory, extract the date the photo was taken from its EXIF metadata. Then replace the date stamp, which is assumed to exist in the filename, by the date the photo was taken. A trick from https://unix.stackexchange.com/a/9256 is used to split the date into its components.

Rename files in batch

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"

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

Create a transition between two videos
We take the first 50 frames of a.mp4 for track a, and 24 blank frames followed by b.mp4 for track b. We then create a transition from track a to track b starting from frame 25 and ending at frame 49. The output is stored in out.mp4 To view the results without saving remove "-consumer avformat:out.mp4" from the end. Documentation of the mlt framework and the melt command can be found here: http://www.mltframework.org/bin/view/MLT/Documentation

Use Linux coding style in C program
put "-linux" option into $HOME/.indent.pro to make it default

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"

Get info about remote host ports and OS detection
Where < target > may be a single IP, a hostname or a subnet -sS TCP SYN scanning (also known as half-open, or stealth scanning) -P0 option allows you to switch off ICMP pings. -sV option enables version detection -O flag attempt to identify the remote operating system Other option: -A option enables both OS fingerprinting and version detection -v use -v twice for more verbosity. $ nmap -sS -P0 -A -v < target >

List symbols from a dynamic library (.so file)
You can get what functions at which addresses are inside a dynamic link library by this tool.

copy/mkdir and automatically create parent directories
The --parents option will cause cp or mkdir to automatically create the parent directory structure. $mkdir --parents /one/two/three/dir will create /one, /one/two, and /one/two/three as needed before creating dir. cp will copy files with their full directory structure into the target directory with this option. Thanks to Peter Leung at: http://linuxcommando.blogspot.com/2007/11/use-of-parents-flag-in-mkdir-and-c.html which has good examples of usage.


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