Larry Bates wrote:
> Shriphani wrote:
>> Hello all,
>> I have a problem here. I have a list named list_of_files which
>> contains filenames with their timestamps attached to the name. If I
>> have a string "fstab", and I want to list out the files in whose names
>> the word fstab appears should I go about like this :
>>
>> def listAllbackups(file):
>> list_of_files = os.listdir("/home/shriphani/backupdir")
>> for element in list_of_files:
>> if element.find(file) != -1:
>> date = ###
>> time = ####
>> return (date, time)
>>
>> The major trouble is that the return statement causes it to exit after
>> attempt one. How do I use the yield statement here?
>>
>> Regards,
>> Shriphani Palakodety
>>
>
> You should take a quick look at glob(). You may be able to use it to make
> life
> a lot easier. Here is how you would do it if all your backup files begin with
> fstab.
>
> import glob
> list_of_backup_files=glob.glob('/home/shriphani/backupdir/glob*')
>
> If "fstab" can appear anywhere in the filename, this might not work for you.
>
I don't see why
list_of_backup_files=glob.glob('/home/shriphani/backupdir/*fstab*')
shouldn't work. However, t answer the OP's question about yield (which
nobody seems to have done fully yet):
1. Rewrite the function to become a generator function:
def listAllbackups(file):
list_of_files = os.listdir("/home/shriphani/backupdir")
for element in list_of_files:
if file in element: # tidied this up too
date = 1 ###
time = 2 ####
yield (date, time)
2. Create a generator by calling the function:
list_of_backup_files = listAllbackups("fstab")
3. Use the generator in an iterative context:
for file in list_of_backup_files:
# do something
regards
Steve
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