# filecmp --- File and Directory Comparisons

> synopsis: Compare files efficiently. Source code: Lib/filecmp.py The !filecmp module defines functions to compare files and directories, with various optional time/correctness trade-offs. For comparing files, see also the difflib module. The !filecmp module defines the following functions Compare th

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synopsis: Compare files efficiently.

Source code: Lib/filecmp.py

The !filecmp module defines functions to compare files and directories, with various optional time/correctness trade-offs. For comparing files, see also the difflib module.

The !filecmp module defines the following functions

Compare the files named f1 and f2, returning True if they seem equal, False otherwise.

If shallow is true and the os.stat signatures (file type, size, and modification time) of both files are identical, the files are taken to be equal.

Otherwise, the files are treated as different if their sizes or contents differ.

Note that no external programs are called from this function, giving it portability and efficiency.

This function uses a cache for past comparisons and the results, with cache entries invalidated if the os.stat information for the file changes. The entire cache may be cleared using clear_cache.

Compare the files in the two directories a and b whose names are given by common.

Returns three lists of file names: match, mismatch, errors. match contains the list of files that match, mismatch contains the names of those that don't, and errors lists the names of files which could not be compared. Files are listed in errors if they don't exist in one of the directories, the user lacks permission to read them or if the comparison could not be done for some other reason.

The shallow parameter has the same meaning and default value as for filecmp.cmp.

For example, cmpfiles('a', 'b', ['c', 'd/e']) will compare a/c with b/c and a/d/e with b/d/e. 'c' and 'd/e' will each be in one of the three returned lists.

Clear the filecmp cache. This may be useful if a file is compared so quickly after it is modified that it is within the mtime resolution of the underlying filesystem.

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