cannot convert ‘std::basic_string’ to ‘const char*’ for argument ‘1’ to ‘int system(const char*)’

The type of expression

" quickscan.exe resolution 300 selectscanner jpg showui showprogress filename '"+name+".jpg'"

is std::string. However function system has declaration

int system(const char *s);

that is it accepts an argumnet of type const char *

There is no conversion operator that would convert implicitly an object of type std::string to object of type const char *.

Nevertheless class std::string has two functions that do this conversion explicitly. They are c_str() and data() (the last can be used only with compiler that supports C++11)

So you can write

string name = "john";

system( (" quickscan.exe resolution 300 selectscanner jpg showui showprogress filename '"+name+".jpg'").c_str() );

There is no need to use an intermediate variable for the expression.

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