getumask - get file creation mask

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GNU                                                2017-09-15                                        GETUMASK(3)

       This is a vaporware GNU extension.

       This function returns the current file creation mask.  It is equivalent to

           mode_t getumask(void)
           {
               mode_t mask = umask( 0 );
               umask(mask);
               return mask;
           }

       except that it is documented to be thread-safe (that is, shares a lock with the umask(2) library call).

       getumask - get file creation mask

       This  function is documented in the glibc manual, but, as at glibc version 2.24, it is not implemented on
       Linux.  (See umask(2) for a thread-safe method of discovering a process's umask.)

umask(2)

#define_GNU_SOURCE             /* See feature_test_macros(7) */
       #include<sys/types.h>#include<sys/stat.h>mode_tgetumask(void);