Example 1: Python program to illustrate Append vs write mode.
Python3
file1 = open ( "myfile.txt" , "w" ) L = [ "This is Delhi \n" , "This is Paris \n" , "This is London" ] file1.writelines(L) file1.close() # Append-adds at last file1 = open ( "myfile.txt" , "a" ) # append mode file1.write( "Today \n" ) file1.close() file1 = open ( "myfile.txt" , "r" ) print ( "Output of Readlines after appending" ) print (file1.read()) print () file1.close() # Write-Overwrites file1 = open ( "myfile.txt" , "w" ) # write mode file1.write( "Tomorrow \n" ) file1.close() file1 = open ( "myfile.txt" , "r" ) print ( "Output of Readlines after writing" ) print (file1.read()) print () file1.close() |
Output:
Output of Readlines after appending This is Delhi This is Paris This is LondonToday Output of Readlines after writing Tomorrow
Python append to a file
While reading or writing to a file, access mode governs the type of operations possible in the opened file. It refers to how the file will be used once it’s opened. These modes also define the location of the File Handle in the file. The definition of these access modes is as follows:
- Append Only (‘a’): Open the file for writing.
- Append and Read (‘a+’): Open the file for reading and writing.
When the file is opened in append mode in Python, the handle is positioned at the end of the file. The data being written will be inserted at the end, after the existing data.