c - How to make a pointer to a variable whose address is stored in a char array? -


i have program in have stored address of variable "var" in char array this:

int var = 10; //defined in somefile sprintf(varaddress,"%p",&var)

so varaddress stores address of var (e.g. "0x7fff22b823dc").

is there way can use varaddress create pointer variable var?

assuming format of string matches implementation-defined format supported %p format conversion, can parse pointer follows:

int var = 10; // writing address string char buf[100]; sprintf(buf, "%p", (void*)&var); printf("address string: %s\n", buf); // reading address void *ptr; sscanf(buf, "%p", &ptr); int *vptr = ptr; printf("got address back: %p\n", (void*)vptr);

demo.

note unless value of pointer came running process itself, attempt @ dereferencing pointer undefined behavior. moreover, object pointer retrieve string must still exist, , type of pointer must match type of object. these constraints make hard envision use case in reading pointer string serve practical purpose.


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