Emulating the 'head' command of Unix in Python
Emulating the 'head' command of Unix in Python: In Unix, the head -n fileName command displays the first n lines of the file fileName. Write a program in Python to emulate the same functionality.
Emulating the 'head' command of Unix in Python
# Ask the user for the filename whose head is to be displayed, and the number of lines comprising the head.
# Output the first whatever-the-input lines.
fileName = input('Please enter the name of the file you wish view the head of: ')
numberOfLines = int(input('Please enter the number of lines in the head that you wish to view: '))
fileHandler = open( fileName, 'r' )
# list to store the head
lines = []
# using a while loop and readline() function, read only a fixed number of lines and append to above list
while len(lines) < numberOfLines:
lines.append(fileHandler.readline())
fileHandler.close()
# Some text to replicate Unix command syntax.
print('\nExecuting command: head -' + str(numberOfLines) + " " + fileName + "\n")
# displaying the head
for line in lines:
print(line, end="")
Try it here.
See also: