S_ISDIR

S_ISDIR
S_ISDIR checks the file mode m to see whether the file is a directory. If so it returns True
freepascal.org

#ifndef S_ISDIR
#define S_ISDIR(x) (((x) & S_IFMT) == S_IFDIR)
#endif

#ifndef S_ISREG
#define S_ISREG(x) (((x) & S_IFMT) == S_IFREG)
#endif

mail.python.org

#ifndef S_ISDIR
#define S_ISDIR(mode)  (((mode) & S_IFMT) == S_IFDIR)
#endif

#ifndef S_ISREG
#define S_ISREG(mode)  (((mode) & S_IFMT) == S_IFREG)
#endif

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