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In this example, a file name is supplied to fopen() to create and open for writing. HowerverHowever, there is no gauruntee guaruntee that the file referenced by file_name does not exist prior to calling fopen(). This may cause an unintended file to be overwritten.
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Compliant Solution 1.
The open() function (defined in the POSIX standardOpen Group 04b) provides a a way to test for file existence . If the O_CREAT and O_EXCL flags are used together, the open() function will fail if the file file specified by file_name already exists.
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