fnmatch - Unix Filename Pattern Matching in Python

Wildcards in the style of the Unix shell are matched using this module. When a single file name matches a pattern, the function fnmatch() returns TRUE; otherwise, it returns FALSE.

When the operating system has a case-sensitive file system, the comparison is case-sensitive.

Shell-style wildcards employ the following special characters and their purposes:

• '*' - matches everything
• '?' - matches any single character
• '[seq]' - matches any character in seq
• '[!seq]' - matches any character not in seq

For a literal match, the meta-characters need to be enclosed in brackets. For instance, the character "?' matches "[?]".

Methods Offered By the fnmatch Module

fnmatch.fnmatch(filename, pattern):

This function yields a boolean result based on whether the supplied filename string matches the pattern string. Prior to the comparison, the parameters will be normalized to all lower- or upper-case if the operating system is case-insensitive.

Example: The script would be to look for any files that finish in ".py" and begin with "fnmatch."

Program Explanation:

This Python application shows how to filter and match filenames according to a given pattern using fnmatch. fnmatch(). The 'fnmatch_*.py' pattern is used to determine if each filename in the current directory matches it. This is done using the fnmatch module. Next, a boolean value indicating whether or not each filename matches the pattern is printed with the filename. Using the program to filter and manipulate files according to particular naming patterns is helpful.

Output:

 
$ python fnmatch_fnmatch.py
Pattern: fnmatch_*.py
Filename: __init__.py               False
Filename: fnmatch_filter.py         True
Filename: fnmatch_fnmatch.py        True
Filename: fnmatch_fnmatchcase.py    True
Filename: fnmatch_translate.py      True
Filename: index.rst                 False   

fnmatch.fnmatchcase(filename, pattern):

This method returns a boolean result after carrying out a case-sensitive comparison and determining if the supplied filename string matches the pattern string.

Example: Regardless of the filesystem and operating system settings, a script for a case-sensitive comparison.

Program Explanation:

This Python program tells the best way to coordinate filename designs that are case-delicate with fnmatch. fnmatchcase(). The fnmatch module is utilized to decide whether each filename in the ongoing catalog compares to the case-delicate example 'FNMATCH_*.PY' that is provided. Then, a boolean worth showing whether every filename coordinates the example is printed with the filename. Fnmatch. fnmatchcase() is useful in circumstances where matching relies upon the distinction between capitalized and lowercase characters since it is case-delicate.

Output:

 
$ python fnmatch_fnmatchcase.py
Pattern: FNMATCH_*.PY
Filename: __init__.py               False
Filename: fnmatch_filter.py         FalseFilename: FNMATCH_FNMATCH.PY        True
Filename: fnmatch_fnmatchcase.py    False
Filename: fnmatch_translate.py      False
Filename: index.rst                 False   

fnmatch.filter(names, pattern):

The subset of the list of names supplied in the function that matches the specified pattern is returned by this function.

Use several file extensions to filter files, for example.

Program Explanation:

This Python application exhibits how to channel a rundown of filenames utilizing fnmatch. filter() and a given example. The application utilizes os. listdir('.') to get a rundown of filenames from the ongoing catalog and build an example called "fnmatch_*.py." The filter function is then used to find and print the subset of filenames that match the pattern. The fnmatch. filter() capability successfully decreases the number of filenames in the rundown, offering a useful strategy for extricating documents that match a predetermined example.

Output:

 
$ python fnmatch_filter.py
Pattern: fnmatch_*.py
Files   : ['__init__.py', 'fnmatch_filter.py', 'fnmatch_fnmatch.py', 
'fnmatch_fnmatchcase.py', 'fnmatch_translate.py', 'index.rst']
Matches : ['fnmatch_filter.py', 'fnmatch_fnmatch.py',
'fnmatch_fnmatchcase.py', 'fnmatch_translate.py']   

fnmatch.translate(pattern):

The shell-style pattern is turned by this method into a regular expression that can be used with re. match(), which matches just at the beginning of the string, not at the beginning of each line.

Program Explanation:

The utilization of fnmatch. translate() to change a shell-style trump card design ('*.txt') into a customary articulation is exhibited in this Python program. From that point onward, a regex object is made by gathering the standard articulation utilizing the re. compile() strategy. As well as printing the deciphered regex design, the program additionally decides whether the regex design matches the string "foobar.txt.". The conversion of shell-style wildcard patterns into regex patterns is made simpler by the function fnmatch.translate(), giving Python programmers more control over the creation of more complex matching scenarios.

Output:

 
'(?s:.*\\.txt)\\Z'
_sre.SRE_Match object; span=(0, 10), match='foobar.txt'