hello all,
my question is not about How code can be rewritten, i just wanna know even though i am not using read only memory of C (i have declared str[20]) why this function gives me segfault and the other code executes comfortably though both code uses same pointer arithmetic.
Code:
#include<stdio.h>
#include<string.h>
void reverse(char*);
int
main()
{
char str[20];
scanf("%s",str);
printf("original string is %s :\n",str);
reverse(str);
printf("reverse string is %s :",str);
return 0;
}
void reverse(char* s)
{
int n,mark,temp;
n = mark = strlen(s);
for(;s < (s + n/2);++s)
{
temp = *s;
*s = *(s + (--mark));
*(s + mark) = temp;
}
return;
}
i am having a string like
" X1 " ---> string lenght is 30
I have stored this to a chararry . ref
so here ref = " X1 "
now i trim the left space by my function . Si the string now becomes
"X1 " ---> string lenght is 15... (3 Replies)
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Hi,
Can any one tell me why my following program is crashing?
#include <iostream>
using namespace std;
class CA {
public:
const static int i;
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I'm newbie learner. My all friend use windows just only me use linux.
so i can't solve any problem by myself. i need a solution.
how can i use pointer as a string.
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{
char *s='\0';
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return 0;
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This code work on... (6 Replies)
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Discussion started by: Azrael
6 Replies
LEARN ABOUT OSX
mvinnstr
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)
09-16-2011
and the other code executes comfortably though both code uses same pointer arithmetic.