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returning a string

returning a string

returning a string

(OP)
Hi,

   I have a doubt, in the following program prints the string returned by throwstring()function.

   The string which the function is returning local to the function or outside of the function.

   Can somebody throw light on underlying mechanism..

    
************************************************
   main()
   {
      char* throwstring();
      printf("%s\n", throwstring());
    }
    
    char *throwstring()
     {
       return "I'm from throwstring func";
     }

**************************************************


Thanks in Advance

RE: returning a string

Unless the char * in throwstring() is defined as static, you're going to end up with something other than what you want in short order, once the area of memory where the local char * was stored is overwritten.  By declaring a static char * or static char[], the memory is allocated in a different area than with local variables.

If you want to keep the value to work with you should strcpy the return value from a function if the value can change upon subsequent function calls.

Lee

RE: returning a string

Your program is presently returning a pointer to a string constant, so there is no problem with disappearing storage.  All string constants are stored in memory which exists for the life of the program.

If you had a true local array, then what trollacious was saying about static would apply.

--
If you dance barefoot on the broken glass of undefined behaviour, you've got to expect the occasional cut.

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