infinite loop in recursive function
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This works (notice the str+1 in the last line):


Code:
char *strchr( char*str, char ch)
{
   if (*str == '\0')
   return NULL;

   if (*str == ch)
   return str;
   
   strchr (str+1, ch);
   
}


But this doesn't:


Code:
char *strchr( char*str, char ch)
{
   if (*str == '\0')
   return NULL;

   if (*str == ch)
   return str;
   
   strchr (str++, ch);
   
}


Is it because using str++ causes str to be used throughout the function and only incremented in the end, after the strchr(str++,ch) line, causing the non incremented str to be sent to all functions and causing an infinite loop?
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There are two forms of the ++ operator: prefix, and postfix. They return different values. The postfix version updates the variable but returns the old value as the value of the expression. The prefix version updates the variable and returns the new value as the value of the expression.

This code:

Code:

void plusplusfun(){
int a = 0;
int b;
int c;

b = a++;
c = ++a;

printf("a = %d; b = %d; c = %d\n",a,b,c);
}

will print out:
Quote:

a = 2; b = 0; c = 2;
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