Commands tagged usage (8)

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Produce 10 copies of the same string

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" }

Burst a Single PDF Document into Single Pages and Report its Data to doc_data.txt
Require the pdftk package It ll split each page in your pdf file , into a new pdf file and report info on doc_data.txt

Get AWS temporary credentials ready to export based on a MFA virtual appliance
You might want to secure your AWS operations requiring to use a MFA token. But then to use API or tools, you need to pass credentials generated with a MFA token. This commands asks you for the MFA code and retrieves these credentials using AWS Cli. To print the exports, you can use: `awk '{ print "export AWS_ACCESS_KEY_ID=\"" $1 "\"\n" "export AWS_SECRET_ACCESS_KEY=\"" $2 "\"\n" "export AWS_SESSION_TOKEN=\"" $3 "\"" }'` You must adapt the command line to include: * $MFA_IDis ARN of the virtual MFA or serial number of the physical one * TTL for the credentials

list folders containing less than 2 MB of data
This command will search all subfolders of the current directory and list the names of the folders which contain less than 2 MB of data. I use it to clean up my mp3 archive and to delete the found folders pipe the output to a textfile & run: $ while read -r line; do rm -Rv "$line"; done < textfile

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

Figure out what shell you're running

recursively remove BOM

Create a new file

'hpc' in the shell - starts a maximum of n compute commands modulo n controlled in parallel, using make
this oneliner uses make and it's jobserver for parallel execution of your script. The '-j' flag for make defines number of subprocesses to launch, '-f' tells make use stdin instead of Makefile. Also make have neat flag '-l', which "Specifies that no new jobs (commands) should be started if there are others jobs running and the load is at least load (a floating-point number)." Also you can use plain Makefile, for better readability: targets = $(subst .png,.jpg,$(wildcard *.png)) $(targets): echo convert $(subst .jpg,.png,$@) $@ all : $(targets)


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