#!/bin/bash

#Print the system date and time in seconds since 1970-01-01 00:00:00 UTC

startTime=$(date +%s);

#We pick a random number between 1 and 10.

#Then we delay the execution for that amount of seconds.

sleep $(( (RANDOM % 10) + 1 ));

endTime=$(date +%s);

#Subtract endTime from startTime to get the total execution time

totalTime=$(($endTime-$startTime));

echo "Process finished after $totalTime seconds";

exit 0;

#!/bin/bash

#This variable expands to the number of seconds since the shell was started.

#We set it to 0, forcing the shell to continue counting from there.

SECONDS=0;

#We pick a random number between 1 and 10.

#Then we delay the execution for that amount of seconds.

sleep $(( (RANDOM % 10) + 1 ));

echo "Process finished after $SECONDS seconds";

exit 0;

#!/bin/bash

#The bash time command reports the time consumed by pipeline's execution

#When time command is executed without its complete path, then the bash built-in time command is executed, instead of the GNU time command.

#We will use the bash time command in this example and we will use it to run a whole block of commands.

#We change the output format of time to print elapsed real time in seconds.

TIMEFORMAT="%E";

#We pick a random number between 1 and 10.

#Then we delay the execution for that amount of seconds.

totalTime=`time ( sleep $(( (RANDOM % 10) + 1 )) ) 2>&1`;

#Please note that time command will return the time in seconds as a float (i.e. there will be decimal places. e.g. 1 will be printed as 1.00).

#This will happen as time has build-in more precision than the first two methods presented here.

echo "Process finished after $totalTime seconds";

totalTimeBlock=`time (

    sleep $(( (RANDOM % 10) + 1 ));

    sleep $(( (RANDOM % 10) + 1 ));

) 2>&1`;

echo "Block finished after $totalTimeBlock seconds";

exit 0;

#!/bin/bash

#The time command runs the specified program command with the given arguments.

#When time command is executed without its complete path (in our case it was /usr/bin/time), then the bash built-in time command is executed, instead of the GNU time command.

#To make sure we use the GNU time command, we use which to get the full path of the time command.

time=`which time`;

#We pick a random number between 1 and 10.

#Then we delay the execution for that amount of seconds.

#We change the output format of time to print elapsed real time in seconds.

totalTime="$( $time -f '%e' sleep $(( (RANDOM % 10) + 1 )) 2>&1 1>/dev/null )";

#Please note that time command will return the time in seconds as a float (i.e. there will be decimal places. e.g. 1 will be printed as 1.00).

#This will happen as time has build-in more precision than the first two methods presented here.

echo "Process finished after $totalTime seconds";

exit 0;