my hitech compiler is generating warninig illegal conversion of pointer to

[zia]

(warning is illegal conversion of pointer to integer)
char *pch;
char j=0;
pch=strchr(Rx1Buffer,'$');
j=pch;

 

[internetuser2k12]

I think it is not

 j=pch

but

 j=*pch

 

[zia]

u r right but i not getting accurate value of j. suppose *pch="123$asdfnbx is " if i am using
pch=strchr(Rx1Buffer,'$');
j=pch;
then it must have to give j=3 or j=4 as according to position but it gives different value as like 156 etc.

 

[internetuser2k12]

try to change

 pch=strchr(Rx1Buffer,'$');

to

 *pch=strchr(Rx1Buffer,'$');

Can you tell what does strchr(Rx1Buffer,'$'); function do?

 

[zia]

function
strchr
<cstring>
const char * strchr ( const char * str, int character );
char * strchr ( char * str, int character );
Locate first occurrence of character in string
Returns a pointer to the first occurrence of character in the C string str.

The terminating null-character is considered part of the C string. Therefore, it can also be located in order to retrieve a pointer to the end of a string.

Parameters
str
C string.
character
Character to be located. It is passed as its int promotion, but it is internally converted back to char for the comparison.

Return Value
A pointer to the first occurrence of character in str.
If the character is not found, the function returns a null pointer.

Portability
In C, this function is only declared as:

char * strchr ( const char *, int );

instead of the two overloaded versions provided in C++.

Example
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/* strchr example */
#include <stdio.h>
#include <string.h>

int main ()
{
char str[] = "This is a sample string";
char * pch;
printf ("Looking for the 's' character in \"%s\"...\n",str);
pch=strchr(str,'s');
while (pch!=NULL)
{
printf ("found at %d\n",pch-str+1);
pch=strchr(pch+1,'s');
}
return 0;
}


Output:

Looking for the 's' character in "This is a sample string"...
found at 4
found at 7
found at 11
found at 18

 

[zuisti]

(warning is illegal conversion of pointer to integer)
char *pch;
char j=0;
pch=strchr(Rx1Buffer,'$');
j=pch; // ????

As can be seen in your example, the correct solution is:

j = pch - Rx1Buffer ; // + 1 (if the first pos is equal to 1)

 

[zia]

j = pch - Rx1Buffer ;
working fine
but plz help me to understand zuisti,plz.

 

[FvM]

Besides the erroneous j = pch, I'm unable to locate a problem or question addressed in your posts.

 

[zia]

j = pch - Rx1Buffer ;
i m not able to understand this logic

 

[internetuser2k12]

char *strchr(char *ptr, char chr);

Description Function locates the first occurrence of character chr in the string ptr. The function returns a pointer to the first occurrence of character chr, or a null pointer if chr does not occur in ptr. The terminating null character is considered to be a part of the string.

Example

 char txt[] = "PIC18F4550";
char *res;

res = strchr(txt, '4');  // routine will locate the character '4' in the 'txt' string, and return the address of the character

 pch=strchr(Rx1Buffer,'$');

here '$' is searched and the address of '$' character in Rx1Buffer is assigned to pointer pch

If Rx1Buffer starts at address 0x00 and the location of '$' character in the RxBuffer is at address 0x08 then pch will be equal to 0x08


@zuisti

Can we write

 j = pch - Rx1Buffer ;

as

 j = strchr(Rx1Buffer,'$') - Rx1Buffer ;

?????

 

[zia]

thanx a lot u have solved my confusion

 

[zuisti]

@zuisti
Can we write

 j = pch - Rx1Buffer ;

as

 [COLOR="#FF0000"]j = strchr(Rx1Buffer,'$') - Rx1Buffer ;[/COLOR]

?????

Yes, of course it is also a possible (and more elegant) solution but only if the first matched character's position is wanted, else use the intermediate 'pch' variable too (in a loop as in the example).