glibc

Numeric conversion functions

atof, atoi, atol, and atoll are UNSAFE: If the value of the result cannot be represented, the behavior is undefined

Path resolution vs. path canonicalization

What's the different b/w canonicalize_file_name() ( realpath()) and readlink()?

• readlink() need as input a symbolic link, and jut read its value. Period.

• canonicalize_file_name() / realpath():

• always returns an absolute file path.
• recursively resolves all symbolic link.
• does not accept circular loops in symbolic link.
• does not accept symbolic link pointing to non-existing files.
• to succeed, it requires the resolved path to exist.