How to resolve “ invalid conversion from 'const char' to 'LPSTR {aka char}' [-fpermissive] "

Question

I use Qt Creator and this code :

CreateProcess(NULL,string("curl -F \"api_key=XXX\" -F \"filetype=mp3\" -F \"track=@"+execpath+"\\sound.mp3\" \"http://developer.echonest.com/api/v4/track/upload\"").c_str(), NULL, NULL, TRUE, CREATE_NO_WINDOW, NULL, NULL, &startupinfo, &procinfo); // Send sound.mp3 to be analyzed by Echonest

generate this issue:

invalid conversion from 'const char*' to 'LPSTR {aka char*}

How to solve it?

Note that I have defined :

DEFINES -= UNICODE

in my .pro file

solved, I've converted to LPSTR : CreateProcess(NULL,(LPSTR) string("... — AmirH, Feb 22 '14 at 17:53
Don't do that; it's not a solution. If the parameter is non-const, it means the function can change it. You don't want it changing a string's `c_str()`. Give the function something that can be modified. — chris, Feb 22 '14 at 17:56
Qt Creator is an IDE. It's use is not very relevant here. Perhaps it is a Qt project - then you should be using `QProcess`. — Kuba hasn't forgotten Monica, Feb 22 '14 at 23:21

mike.dld · Accepted Answer · 2014-02-22T18:11:13.033

You need to read documentation on CreateProcess() carefully. Second argument is marked as inout, meaning the function would (in this case, could) modify the value pointed to.

If you're going to make a cast the way you mention in comments, it is better to not only add a comment but also probably use ANSI function explicitly (thus calling CreateProcessA()) just in case.

Also, Qt has its own way of creating processes. You could refer to QProcess documentation.

How to resolve “ invalid conversion from 'const char*' to 'LPSTR {aka char*}' [-fpermissive] "

1 Answers1

How to resolve “ invalid conversion from 'const char' to 'LPSTR {aka char}' [-fpermissive] "