Let there are some situations in which you have to save your output in a file ( generally called log file). Output can be user details ( username, password, Gmail, etc. ), products record ( buying or selling any goods ), or simply any kind of data that you can store in a log file.
Let see how to write the output of the bash command into a log file.
Example 1 :
In this example, we can store the names of two-person in a log file.
First, create a log file named ” Log.txt ” by the following command
$ touch Log.txt
Note: ” Log.txt ” will store the output.
Now, create a bash script file by the following command
$ touch Name.sh
Note: ” Name.sh ” It is a bash script file that will take two names from the user and store it into ” Log.txt “
Now, open ” Name.sh ” in a text editor
$ nano Name.sh
Now write the following bash script in ” Name.sh ”
#!/bin/bash echo "Enter First Person Name : " # It will take input from user i.e. # First Person Name read FName # It store First Person Name in Log.txt echo "First Person Name : $FName">Log.txt echo echo "Enter Second Person Name : " # It will take input from user i.e. # Second Person Name read SName # It append Second Person Name in Log.txt echo "Second Person Name : $SName">>Log.txt
Note: Here, ‘ > ‘ it will create a new file with a specified name if the file does not exist and it will use to overwrite the data stored in the file ( i.e. ” Log.txt “). And ‘ >> ‘ it will create a new file with a specified name if the file does not exist and it will append the output data in the file ( i.e. ” Log.txt ” )
Now save and run ” Name.sh ” by the following command
$ chmod +x ./Name.sh $ ./Name.sh
Output :
As it is shown in the above picture that we take two inputs ” Sahil ” and ” Rakesh “. The output name will store in ” Log.txt “.
The above picture shows the ” Log.txt ” file that the output will store in the log file ( i.e. ” Log.txt ” ).
Example 2 :
In this example, we can store the student details
First, create a log file named ” Student_log.txt ” to store output using the below command
$ touch Student_log.txt
Now, create a bash script file by the following command
$ touch Student_details.sh
Now, open ” Student_details.sh ” in text editor
$ nano Student_details.sh
Now, write the following bash script in ” Student_details.sh ”
#!/bin/bash # Save Date and Time of the bash script # execution inside Student_log.txt date>Student_log.txt echo echo "Student Details">>Student_log.txt echo "Name Of Student : " read Name # Store Name in Student_log.txt echo "Student Name : $Name">>Student_log.txt echo echo "Roll No. Of Student : " read RNo # Store Roll No. in Student_log.txt echo "Roll No. : $RNo">>Student_log.txt echo echo "Marks Obtained : " read OMarks echo "Total Marks : " read TMarks # calculate Percentage Percentage=$((OMarks*100/TMarks)) # Here it store Percentage in Student_log.txt echo "Percentage : $Percentage">>Student_log.txt
Note: Here ” date ” command will show the date as well as the time of the execution of the ” date ” command
Now save and run ” Student_details.sh ” by the following command
$ chmod +x ./Student_details.sh $ ./Student_details.sh
Output :
As it is shown in the above picture that we store the date of program execution and student details as well as their percentage. The output will store in ” Student_log.txt “.
The above picture is show ” Student_log.txt “