Commands tagged grep (409)

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Generate random passwords (from which you may select "memorable" ones)
See: "man pwgen" for full details. Some Linux distros may not have pwgen included in the base distribution so you maye have to install it (eg in Mandriva Linux: "urpmi pwgen").

check open ports without netstat or lsof

Watch active calls on an Asterisk PBX
Only the number of calls nothing else.

Random Number Between 1 And 256
It takes a byte from /dev/random whose source is the kernel entropy pool (better source than other solutions).

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

check open ports without netstat or lsof

Detect Language of a string
Usage: $ detectlanguage Example: $ detectlanguage hola

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 pi with specific scale
a() function in bc is for arctangent, available if using -l option included.

Counting the source code's line numbers C/C++ Java
Count your source and header file's line numbers. This ignores blank lines, C++ style comments, single line C style comments. This will not ignore blank lines with tabs or multiline C style comments.


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