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Top Forums Programming Scanf() string pointer problem Post 302874171 by Corona688 on Thursday 14th of November 2013 11:05:39 AM
Old 11-14-2013
char *studentName; is a pointer to a string. What does it point to? Absolutely nothing and nowhere in particular. It might point to invalid memory and crash immediately. It might point to somewhere in your own stack frame, causing it to crash later in fascinating nondeterministic ways.

The correct solution would be to either
1) Use line 8
2) Point it to valid memory with a line like list[x].studentName=malloc(20);

Last edited by Corona688; 11-14-2013 at 12:16 PM..
This User Gave Thanks to Corona688 For This Post:
 

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mvscanw(3XCURSES)					  X/Open Curses Library Functions					 mvscanw(3XCURSES)

NAME
mvscanw, mvwscanw, scanw, wscanw - convert formatted input from a window SYNOPSIS
cc [ flag... ] file... -I /usr/xpg4/include -L /usr/xpg4/lib -R /usr/xpg4/lib -lcurses [ library... ] c89 [ flag... ] file... -lcurses [ library... ] #include <curses.h> int mvscanw(int y, int x, char *fmt, ...); int mvwscanw(WINDOW *win, int y, int x, char *fmt, ...); int scanw(char *fmt, ...); int wscanw(WINDOW *win, char *fmt, ...); PARAMETERS
y Is the y (row) coordinate of the position of the character to be read. x Is the x (column) coordinate of the position of the character to be read. fmt Is a scanf() format string. win Is a pointer to the window in which the character is to be read. DESCRIPTION
These functions are similar to scanf(3C). Their effect is as though mvwgetstr(3XCURSES) were called to get a multi-byte character string from the current or specified window at the current or specified cursor position, and then sscanf() were used to interpret and convert that string. RETURN VALUES
Upon successful completion, these functions return OK. Otherwise, they return ERR. ERRORS
No errors are defined. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |Standard | +-----------------------------+-----------------------------+ |MT-Level |Unsafe | +-----------------------------+-----------------------------+ SEE ALSO
getnstr(3XCURSES), libcurses(3XCURSES), printw(3XCURSES), scanf(3C), wcstombs(3C), attributes(5), standards(5) SunOS 5.11 5 Jun 2002 mvscanw(3XCURSES)
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