The method ftruncate() truncates the file corresponding to file descriptor fd, so that it is at most length bytes in size.
fd -- This is the file descriptor, which needs to be truncated.
length -- This is the length of the file where file needs to be truncated.
#!/usr/bin/python import os, sys # Open a file fd = os.open( "foo.txt", os.O_RDWR|os.O_CREAT ) # Write one string os.write(fd, "This is test - This is test") # Now you can use ftruncate() method. os.ftruncate(fd, 10) # Now read this file from the beginning. os.lseek(fd, 0, 0) str = os.read(fd, 100) print "Read String is : ", str # Close opened file os.close( fd ) print "Closed the file successfully!!"
When we run above program, it produces following result:
Read String is : This is te Closed the file successfully!!