post  L-value error in threads and processess

charlie (37)
During compilation I receive a compiler error
#include<windows.h>
#include<iostream>
using namespace std;
typedef struct{
int a;
char name[7];
}params;
void print(params*lparam)
{
for(int i=0;i<10;i++){
cout<<"A in struct params is "<<lparam->a<<endl;
cout<<"Name in struct params is "<<lparam->name<<endl;
Sleep(5000);
}
void main()
{
params myparams;
myparams.a=1000;
myparams.name="joseph";
HANDLE threadhandle;
DWORD threadID;
threadhandle=CreateThread(0,0,(LPTHREAD_START_ROUTINE)print,&myparams,0,&threadID);
if(INVALID_HANDLE_VALUE==threadhandle)
{
cerr<<"Thread not created..."<<endl;
return -1;
}
//if threadcreated wait for execution to finish
while(WaitForSingleObject(threadhandle,9000)==WAIT_TIMEOUT){
cout<<"function execution fcompleted..."<<endl;
}
return 0;
}

I'm using VC++ 6.0 I receive the folowing compiler error and its the first I come across with such errors can somebody help...
the error says:
errorC2106:'=' :left operand must be l-value
From what I know a left operand is a variable or address.Thanks
Last edited on
Grey Wolf (1344)
There seem to be a number of thing with your code:

1: typedef stuct I assume that should be typedef struct
2: void print(param*lparam), should that be params?
3: You open a block { in the print function but do not close it.
4: You have main defined as void and try to return a value;
and finally the bit that I assume is giving the error is myparams.name="joseph";, you will need to use a function to copy "joseph" into "myparams.name".

PS. please use code tags to post code: [code]your code goes here[/code]
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charlie (37)
Thank for your advice It 's working .I have used the strcpy() function
charlie (37)
Thanks for your advice It 's working .I have used the strcpy() function also I would like to know what the error meant I mean the lvalue error and how I get away with it.
Last edited on
Grey Wolf (1344)
error C2106:'=' :left operand must be l-value

An l-value is one that can appear on the left side of an assignment, so it is basically saying you can not assign a new value to the left hand side.

I must admit I would have expected the error to be along the lines of
error C2440: '=' : cannot convert from 'const char [7]' to 'char [7]'

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charlie (37)
I don't know but that is way it appeared on my compiler error.hope you don't mind me asking which compiler are you using ?mine is vc++ 6.0 ...
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Grey Wolf (1344)
Visual Studio Team System 2008 and Visual Studio 2005 Team Edition for Software developers. I also have Visual Studio 6 Enterprise Edition, for the older projects that have not been migrated.
charlie (37)
Have done DirectX before? I'm still learning C++ I can say.But know I want to How my OS works before decide to something else.Your advice..!what should I do then...
Zaita (2112)
I would suggest using strncpy() instead of strcpy() or snprintf() (not sprintf().

strcpy() is not save from buffer overflows, it's generally considered bad practice to use it.

Edit: I'd also suggest using string instead of character arrays and pointers to characters. (e.g char *)
Last edited on
charlie (37)
Thanks Zaita...OK now it's time for your advice ...!
Grey Wolf (1344)
Do you want to know the internal working of Windows, or how to write Windows native code?
charlie (37)
I wanna know how the internal workings of windows......

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