File I/O

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FileIO1.py

#!/usr/bin/env python3;
###############################################################################
# This program simply copies a file to the console character by
# character like the Unix 'cat' program.
# 
# Copyright © 2020 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def readTextFile(filespec) :
	ifh = open(filespec, "r", encoding="utf8")
	c = Utils.getchar(ifh)
	while c != None :
		print(chr(c), end="")
		c = Utils.getchar(ifh)
	ifh.close()

# Begin Main
if (len(sys.argv) != 2) :
	print("Syntax: " + sys.argv[0] + " {filename}")
	sys.exit(1)
filespec = sys.argv[1]
try :
	readTextFile(filespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO2.py

#!/usr/bin/env python3;
###############################################################################
# This program simply copies a file to the console line by line.
# 
# Copyright © 2020 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def readTextFile(filespec) :
	ifh = open(filespec, "r", encoding="utf8")
	line = Utils.getline(ifh)
	while line != None :
		print(line)
		line = Utils.getline(ifh)
	ifh.close()

# Begin Main
if (len(sys.argv) != 2) :
	print("Syntax: " + sys.argv[0] + " {filename}")
	sys.exit(1)
filespec = sys.argv[1]
try :
	readTextFile(filespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO3.py

#!/usr/bin/env python3;
###############################################################################
# This program reads bytes from a file and prints them in decimal format.
# 
# Copyright © 2021 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def readBinaryFile(filespec) :
	ifh = open(filespec, "rb")
	count = 0
	c = Utils.getbyte(ifh)
	while c != None :
		print(str(c) + " ", end="")
		count += 1
		if (count % 20 == 0) :
			print()
		c = Utils.getbyte(ifh)
	if (count % 20 != 0) :
		print()
	ifh.close()

# Begin Main
if (len(sys.argv) != 2) :
	print("Syntax: " + sys.argv[0] + " {filename}")
	sys.exit(1)
filespec = sys.argv[1]
try :
	readBinaryFile(filespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO4.py

#!/usr/bin/env python3;
###############################################################################
# This program simply writes characters from the alphabet to a file.
# 
# Copyright © 2020 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def writeTextFile(filespec) :
	ofh = open(filespec, "w", encoding="utf8")
# Latin alphabet
	for c in range(0x41, 0x5A + 1) :
		print(chr(c), file=ofh, end="")
	print("\n", file=ofh, end="")
# Greek alphabet
	for c in range(0x391, 0x3A9 + 1) :
		print(chr(c), file=ofh, end="")
# Cyrillic alphabet
	for c in range(0x410, 0x42F + 1) :
		print(chr(c), file=ofh, end="")
	print("\n", file=ofh, end="")
# Katakana alphabet
	for c in range(0x30A0, 0x30FF + 1) :
		print(chr(c), file=ofh, end="")
	print("\n", file=ofh, end="")
	ofh.close()

# Begin Main
if (len(sys.argv) != 2) :
	print("Syntax: " + sys.argv[0] + " {filename}")
	sys.exit(1)
filespec = sys.argv[1]
try :
	writeTextFile(filespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO5.py

#!/usr/bin/env python3;
###############################################################################
# This program simply writes lines with the alphabet to a file.
# 
# Copyright © 2020 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def writeTextFile(filespec) :
	ofh = open(filespec, "w", encoding="utf8")
	print("ABCDEFGHIJKLMNOPQRSTUVWXYZ", file=ofh, end="\n")
	print("ΑΒΓΔΕΖΗΘΙΚΛΜΝΞΟΠΡΣΤΥΦΧΨΩ", file=ofh, end="\n")
	print("АБВГДЕЖЗИЙКЛМНОПРСТУФХЦЧШЩЪЫЬЭЮЯ", file=ofh, end="\n")
	print("゠ァアィイゥウェエォオカガキギクグケゲコゴサザシジスズセゼソゾタ", file=ofh, end="\n")
	print("ダチヂッツヅテデトドナニヌネノハバパヒビピフブプヘベペホボポマミ", file=ofh, end="\n")
	print("ムメモャヤュユョヨラリルレロヮワヰヱヲンヴヵヶヷヸヹヺ・ーヽヾヿ", file=ofh, end="\n")
	ofh.close()

# Begin Main
if (len(sys.argv) != 2) :
	print("Syntax: " + sys.argv[0] + " {filename}")
	sys.exit(1)
filespec = sys.argv[1]
try :
	writeTextFile(filespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO6.py

#!/usr/bin/env python3;
###############################################################################
# This program simply writes the bytes 0 - 256 to a binary file.
# 
# Copyright © 2021 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def writeBinaryFile(filespec) :
	ofh = open(filespec, "wb")
	for b in range(0, 255 + 1) :
		ofh.write(b.to_bytes(1, byteorder='big', signed=False))
	ofh.close()

# Begin Main
if (len(sys.argv) != 2) :
	print("Syntax: " + sys.argv[0] + " {filename}")
	sys.exit(1)
filespec = sys.argv[1]
try :
	writeBinaryFile(filespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO7.py

#!/usr/bin/env python3;
###############################################################################
# This program simply copies one file to another, character by
# character like the Unix 'cat' program.
# 
# Copyright © 2020 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def copyTextFile(fromFilespec, toFilespec) :
	ifh = open(fromFilespec, "r", encoding="utf8")
	ofh = open(toFilespec, "w", encoding="utf8")
	c = Utils.getchar(ifh)
	while c != None :
		print(chr(c), file=ofh, end="")
		c = Utils.getchar(ifh)
	ifh.close()
	ofh.close()

# Begin Main
if (len(sys.argv) != 3) :
	print("Syntax: " + sys.argv[0] + " {fromFilespec} {toFilespec}")
	sys.exit(1)
fromFilespec = sys.argv[1]
toFilespec = sys.argv[2]
try :
	copyTextFile(fromFilespec, toFilespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO8.py

#!/usr/bin/env python3;
###############################################################################
# This program simply copies one file to another, line by line.
# 
# Copyright © 2020 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def copyTextFile(fromFilespec, toFilespec) :
	ifh = open(fromFilespec, "r", encoding="utf8")
	ofh = open(toFilespec, "w", encoding="utf8")
	line = Utils.getline(ifh)
	while line != None :
		print(line, file=ofh, end="\n")
		line = Utils.getline(ifh)
	ifh.close()
	ofh.close()

# Begin Main
if (len(sys.argv) != 3) :
	print("Syntax: " + sys.argv[0] + " {fromFilespec} {toFilespec}")
	sys.exit(1)
fromFilespec = sys.argv[1]
toFilespec = sys.argv[2]
try :
	copyTextFile(fromFilespec, toFilespec)
except OSError as ex :
	print("Error: " + str(ex))

FileIO9.py

#!/usr/bin/env python3;
###############################################################################
# This program reads bytes from a binary file and copies them to another file.
# 
# Copyright © 2021 Richard Lesh.  All rights reserved.
###############################################################################

import Utils
import sys

def copyBinaryFile(fromFilespec, toFilespec) :
	ifh = open(fromFilespec, "rb")
	ofh = open(toFilespec, "wb")
	c = Utils.getbyte(ifh)
	while c != None :
		ofh.write(c.to_bytes(1, byteorder='big', signed=False))
		c = Utils.getbyte(ifh)
	ifh.close()
	ofh.close()

# Begin Main
if (len(sys.argv) != 3) :
	print("Syntax: " + sys.argv[0] + " {fromFilespec} {toFilespec}")
	sys.exit(1)
fromFilespec = sys.argv[1]
toFilespec = sys.argv[2]
try :
	copyBinaryFile(fromFilespec, toFilespec)
except OSError as ex :
	print("Error: " + str(ex))

Questions

• {{Who's on first?}}
• {{Who's on second?}}
• {{Who's on third?}}

Projects

More ★'s indicate higher difficulty level.

• Base64 Decoding
• Base64 Encoding
• ChaCha20 Cipher
• Number of Primes
• One-Way Hash
• Palindrome Search
• Spell Checker
• XOR Cipher

References

• [[Python Language Reference]]
• [[Python Standard Library]]
• [[Python at TutorialsPoint]]