Commands by SEJeff (10)

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identify exported sonames in a path
This provides a list of shared object names (sonames) that are exported by a given tree. This is usually useful to make sure that a given required dependency (NEEDED entry) is present in a firmware image tree. The shorter (usable) version for it would be $ scanelf -RBSq -F "+S#f" But I used the verbose parameters in the command above, for explanation.

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" }

Calculate days on which Friday the 13th occurs (inspired from the work of the user justsomeguy)
Friday is the 5th day of the week, monday is the 1st. Output may be affected by locale.

LIST FILENAMES OF FILES CREATED TODAY IN CURRENT DIRECTORY
Then pipe to 'xargs ls' for a familiar listing, possibly using find's -print0 and xarg's -0 options.

Obtain last stock quote from google API with xmlstarlet

Change prompt to MS-DOS one (joke)
This one eliminates the additional backslash at the end (which is not necessary)

Manipulate the metadata when the photo was taken, this will shift with +15hours + 30min

Default value or argument
I used it for this function, which prints hashes: function liner { num_lines=${1:-42} echo printf %${num_lines}s|tr " " "#" echo } Note the colon-dash, instead of the usual colon-equals.

list files recursively by size

See entire packet payload using tcpdump.
This command will show you the entire payload of a packet. The final "s" increases the snaplength, grabbing the whole packet.


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