python - How to read multiple files with error checking? -


i have function reads multiple files. this:

try:     = open("1.txt", "r")     b = open("2.txt", "r")     c = open("3.txt", "r") except ioerror:     print("file {:s} failed".format(a, b or c))

i want can see file failed during reading it. can somehow specify ioerror specified file? mean if ioerror appears in file a, "command1", if in file b, "command2" , on?

the ioerror exception alias of oserror exception, has filename attribute. can use switch behaviour based on file failed:

try:     = open("1.txt", "r")     b = open("2.txt", "r")     c = open("3.txt", "r") except oserror error:     print("file {:s} failed".format(error.filename))

i used name oserror; ioerror deprecated , kept around backwards compatibility, see pep 3151.

demo:

>>> try: ...     open('nonesuch.txt') ... except oserror error: ...     print('file {:s} failed'.format(error.filename)) ...  file nonesuch.txt failed

note open() call throws exception, no assignment has taken place. , because file object can referenced multiple places, including list, there no way map file object or filename name going assign to. if wanted know of a, b or c file object have been bound to, you'd have create own mapping:

filenames = {'1.txt': 'a', '2.txt': 'b', '3.txt': 'c'} print("file {} failed".format(filenames[error.filename]))

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