Attempted to read or write protected memory : C++ Modified Value of Memory -

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• why segmentation fault when writing string initialized “char *s” not “char s[]”? 16 answers

i trim string "char array in c , c++ or char pointer" use function:

inline char * trimright(char * str) {     char * end = str + strlen(str);     while(str != end)     {         end--;         switch(*end)         {             case ' ':             case '\t':             case '\n':             case '\v':             case '\f':             case '\r':             break;             default:                 *(end+1) = '\0';                 return end+1;         }     }     return str; } 

but return error (reason in code *(end+1) = '\0' ) :

an unhandled exception of type 'system.accessviolationexception' occurred in x.exe

additional information: attempted read or write protected memory. indication other memory corrupt.

please me.

no doubt tried call function on string literal, write protected. make sure don't use string literals , fine.

bad:

char *s = "hello   "; trimright(s); 

good:

char s[] = "hello   "; trimright(s); 

also way, function doesn't trim if string spaces. i'm not sure if wanted way, seems should set *str = '\0'; in case.