Question

 void fileNameProcess(char * inputName){
             int size =strlen(inputName);
             bool change=false;
             char * name=inputName;

             for(int i =0; i<size; i++){
                 char temp=* (name+i);
                 if(temp<0x10||temp>0x5b){
                     change=true;
                 }else if(0x19<temp<0x21){
                     change=true;
                 }else if(0x3a<temp<0x41){
                     change=true;
                 }
                 if(change){
                     //*(name+i)='_';
                     memset(name+i, '_', 1);
                     change=false;
                 }
             }

         }

it breaks when i try to set a character in a string (memeset), but i dont understand why it doesnt allow me to do that? why i can allow access to read it but couldnt modify it?
can anyone explain it in memory aspect. i guess it is because the string is passed into the function. but as long as i know the memeory location, i could set it right?

thanks

char * filename= strdup("try1.mat");
    writter.locate(filename);

in locate it assign filename to class memeber char* filepath

Answer 1

This:

if(1 < variable < 2)

Probably doesn’t do what you want. Use:

if(1 < variable && variable < 2)

edit
if(1 < variable < 2) evaluates like this:

if( (1 < variable) < 2)
if( (true) < 2)
//given true is often* assigned a value of 1 this will always be true and
if( (false) < 2)
//false is always zero this will also be true

*I don’t think this is required by the standard so don’t rely on it.