Adapted and simplified from Franck Albinet's exercises available here. Also presented by NSRC at APRICOT 2018.
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In essence to handle files in Python, you first need to open a file (even if it does not exist yet)
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python f = open('log/my_first_file.log', 'w') |
the open
function takes as argument: file name 'log/my_first_file.log'
(relative or full path) and mode: read, write, ...
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Then you need to close the file to free up any system resources taken up by the open file. After calling
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f.close() |
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attempts to use the file object will automatically fail.
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Finally, before creating a folder or a file, we would like to test if it exists already. The code below test it and recap. the whole process:{code
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import os file_path = '/flash/log' try: os.listdir('/flash/log') print('/flash/log file already exists.') except OSError: print('/flash/log file does not exist. Creating it ...') os.mkdir('/flash/log') name = '/my_first_file.log' # Writing with open(file_path + name, 'w') as f: f.write('Testing write operations in a file.') # Reading with open(file_path + name, 'r') as f: print(f.readall()) |
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