kent37 at tds.net
Thu Sep 13 13:01:07 CEST 2007
Christopher Spears wrote:
> I created a script that opens an existing text file,
> allows the user to write over the original contents,
> and then save the file. The original contents are
> then saved in a separate file. Here is the script:
> 'editTextFile.py -- write over contents of existing
> text file'
> import os, string
> # get filename
> while True:
> fname = raw_input('Enter file name: ')
> if not (os.path.exists(fname)):
> print"*** ERROR: '%s' doesn't exist" % fname
> # get file content (text) lines
> all = 
> print "\nEnter lines ('.' by itself to quit).\n"
> # loop until user terminates input
> while True:
> entry = raw_input('> ')
> if entry == '.':
> # write lines to file with NEWLINE line terminator
> print "1) Replace file's contents"
> print "Any other key quits function without replacing
> file's contents"
> choice = raw_input("Make a choice: ")
> if choice == '1':
> fobj = open(fname, 'r')
> fobj_lines = fobj.readlines()
> fobj = open(fname, 'w')
It would be safer to write the '_orig' file before opening the original
file for writing (which erases its contents)
> fname_orig = fname + '_orig'
> fobj_orig = open(fname_orig, 'w')
> stripped_lines = 
> for line in fobj_lines:
This doesn't change line. You need to assign the result back to line:
line = string.strip(line)
line = line.strip()
Note that this will also strip leading and trailing whitespace from the
lines so the copy will not be a duplicate of the original.
A simpler way to copy a file is to read the entire contents using
fobj.read() and write them as a single string. Even easier is to use
shutil.copyfile() which does this for you.
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