HI,
Here is some thing that is puzzling me from a long time.
Can some body explain me this with example.
The question is :-
What is the difference between function pointer and pointer to a function.
Where do we actually use the function pointers and pointer to functions.
Thanks in... (0 Replies)
Hi all
i wonder about function pointers as i never used them in my C code .
could any tell me why and where exactly function pointers come into
picture .
thanq (1 Reply)
Hi I mash with pointers in C. I solve this problem about 5 hours and I don't know how I should continue.
void InsertFirst (tList *L, int val) {
tElemPtr new;
if((new = malloc(sizeof(tElemPtr))) == NULL) Error();
new->data = val;
new->ptr = L->frst;
L->frst = new;... (2 Replies)
I am using a structure defined as follows
struct gene_square
{
double *x;
double *y;
};I have class, with a member function which is a pointer of this type:
gene_square* m_Genes;I am allocating memory in the constructors like this:
m_Genes = new gene_square;
for (ii=0;... (1 Reply)
If one wants to get a start address of a array or a string or a block of memory via a function, there are at least two methods to achieve it:
(1) one is to pass a pointer-to-pointer parameter, like:
int my_malloc(int size, char **pmem)
{
*pmem=(char *)malloc(size);
if(*pmem==NULL)... (11 Replies)
I am new to shared pointer conceot in C++ and hence require some clarification:
For example:
class A
{
public:
virtual ~A()
{
}
int x;
};
typedef boost::shared_ptr<A>... (1 Reply)
I have a special character called ô. When it is declared as a character variable its showing it can be printed. But when it is declared as a character pointer variable its showing it cannot be printed. I am just wondering why its happening like this..
c1 = '@';
c2 = 'ô';
char *fp;
fp="XXô";
if... (1 Reply)
Hello, I read from a book exercise for a challenge. How to print out each letter of char array a by two different pointers pa and ppa in the example?
I have tried my code for letter "r" by testing without full understanding as only the first one worked.
#include<stdio.h>
int main()
{
char... (17 Replies)
Discussion started by: yifangt
17 Replies
LEARN ABOUT OSX
innstr
curs_instr(3X)curs_instr(3X)NAME
instr, innstr, winstr, winnstr, mvinstr, mvinnstr, mvwinstr, mvwinnstr - get a string of characters from a curses window
SYNOPSIS
#include <curses.h>
int instr(char *str);
int innstr(char *str, int n);
int winstr(WINDOW *win, char *str);
int winnstr(WINDOW *win, char *str, int n);
int mvinstr(int y, int x, char *str);
int mvinnstr(int y, int x, char *str, int n);
int mvwinstr(WINDOW *win, int y, int x, char *str);
int mvwinnstr(WINDOW *win, int y, int x, char *str, int n);
DESCRIPTION
These routines return a string of characters in str, extracted starting at the current cursor position in the named window. Attributes are
stripped from the characters. The four functions with n as the last argument return a leading substring at most n characters long (exclu-
sive of the trailing NUL).
RETURN VALUE
All of the functions return ERR upon failure, or the number of characters actually read into the string.
X/Open defines no error conditions. In this implementation, if the window parameter is null or the str parameter is null, a zero is
returned.
NOTES
Note that all routines except winnstr may be macros.
PORTABILITY
SVr4 does not document whether a length limit includes or excludes the trailing NUL.
The ncurses library extends the XSI description by allowing a negative value for n. In this case, the functions return the string ending
at the right margin.
SEE ALSO curses(3X).
curs_instr(3X)