Is it possible to create pointers in C without a specific datatype -


so started programming project, , found out make easier if make pointer without declaring char*, int* , on , specify size somewhere else. searched around couldn't find useful.

right idea make char* , unite them bit shifting , or operations if isn't string. if low level c, language lets me this, prefer not use assembly because isn't cross platform enough.

edit: forget mention should allocate memory @ runtime, , not waste memory want allocate memory depending on size. example want allocate 1 byte char sized values , 2 bytes int sized values , on. size predefined in file, not known until file read should read in runtime rather compiling time.

there generic pointer type in c reason: void *.

you can convert data pointer type implicitly , void *:

char foo[] = "bar"; void *ptr = foo;  // ...  char *str = ptr;

but aware still have know correct type. accessing object through pointer of wrong type undefined behavior.

there 2 things can't void *:

  • you can't pointer arithmetics on (this includes indexing). void incomplete type, doesn't have known size. compilers allow arithmetics on void * assuming size of char, extension , not portable.

  • you can't dereference void *. void "nothing", wouldn't meaningful.


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