#include <stdio.h>
int main ()
{
FILE * pFile;
int n;
char name [100];
pFile = fopen ("myfile.txt", "w");
for (n = 0; n < 3; n++)
{
puts ("please, enter a name: ");
gets (name);
fprintf (pFile, "Name %d [%-10.10s]\n", n, name);
}
fclose (pFile);
return 0;
}
this code gives me a warning in gcc saying 'gets is a dangerous function to use'...is there a workaround for it?
Yes it is fgets. Replace your call to gets with:
fgets(name, 100, stdin)
For more details see the docs - the two are not exactly the same.
Related
The question is pretty basic.
Code:
#include<iostream>
#include<fstream>
using namespace std;
struct Customer
{
char name[20];
char cell[12];
double bal;
};
int get_total_records_from_file(char * filename)
{
// Implement this funtion
return 0;
}
void get_input_from_user(Customer * ptr){
cin.ignore();
for(int i = 0; i < customer_count; i++){
cout<<"Enter Customer Name (1-20 character long)"<<endl;
cin.getline(ptr[i].name,20);
cout<<"Enter Cell No. (11 character long)"<<endl;
cin.getline(ptr[i].cell,20);
cout<<"Enter Initial Balance"<<endl;
cin >> ptr[i].bal;
cin.ignore();
}
}
If I have this error:
main.cpp:22:21: error: ‘customer_count’ was not declared in this scope
what do the various portions of it mean? That is, what's 22? what's 21? etcetra.
I'm trying to make the app using FreeTDS. Following are my code
/*
* Purpose: Test to see if row buffering and blobs works correctly.
* Functions: dbbind dbnextrow dbopen dbresults dbsqlexec dbgetrow
*/
#include "common.h"
#include "stdio.h"
#include<stdlib.h>
#include "readline/readline.h"
#include "readline/history.h"
#include "string.h"
int
main(int argc, char **argv)
{
char failed;
int hasil;
char ch;
char* r = malloc(30);
LOGINREC *login;
DBPROCESS *dbproc;
int i;
int p = 0;
char teststr[1024];
DBINT testint;
read_login_info(argc, argv);
fprintf(stdout, "Starting %s\n", argv[0]);
/* Fortify_EnterScope(); */
while(1)
{
char qrcode[50];
char perintahsql[100] = "select * from REF_COBA where id=";
char *alokasi="";
while(ch != '\n') // terminates if user hit enter
{
ch = getchar();
qrcode[p] = ch;
p++;
}
qrcode[p]='\0';
strcpy(r,qrcode);
alokasi = strsep(&r, ",");
strcpy(r,"");
p=0;
ch = "";
dbinit();
dberrhandle(syb_err_handler);
dbmsghandle(syb_msg_handler);
fprintf(stdout, "About to logon\n");
login = dblogin();
DBSETLPWD(login, PASSWORD);
DBSETLUSER(login, USER);
DBSETLAPP(login, "text_buffer");
//DBSETLHOST(login, "ntbox.dntis.ro");
DBSETLHOST(login, "192.168.1.9");
fprintf(stdout, "About to open\n");
dbproc = dbopen(login, SERVER);
if (strlen(DATABASE))
dbuse(dbproc, DATABASE);
dbloginfree(login);
#ifdef MICROSOFT_DBLIB
dbsetopt(dbproc, DBBUFFER, "100");
#else
dbsetopt(dbproc, DBBUFFER, "100", 0);
#endif
dbcmd(dbproc, strcat(perintahsql,alokasi));
dbsqlexec(dbproc);
if (dbresults(dbproc) != SUCCEED)
{
failed = 1;
fprintf(stdout, "Was expecting a result set.");
exit(1);
}
fprintf(stdout, "select\n");
for (i = 1; i <= dbnumcols(dbproc); i++)
printf("col %d is %s\n", i, dbcolname(dbproc, i));
fprintf(stdout, "setelah for\n");
dbbind(dbproc, 1, INTBIND, 0, (BYTE *) & testint);
dbbind(dbproc, 2, CHARBIND, 0, (BYTE *) teststr);
for (i = 1; i < 2; i++)
{
char expected[1024];
sprintf(expected, "row %03d", i);
if (i % 100 == 0)
{
dbclrbuf(dbproc, 100);
}
if (REG_ROW != dbnextrow(dbproc))
{
failed = 1;
fprintf(stderr, "Failed. Expected a row\n");
//exit(1);
}
else
{
fprintf(stdout, "jalanin usb\n");
printf("Read a row of data -> %d %s\n", (int) testint, teststr);
hasil = system("/opt/usb1rc_linux USB1REL-172 R");
sleep(2);
hasil = system("/opt/usb1rc_linux USB1REL-172 r");
}
}
dbfreebuf(dbproc);
dbexit();
}
return 0;
}
I modified the source from FreeTDS, after compilation there are some warning
bash-4.2# make text_buffer
CC text_buffer.o
text_buffer.c: In function 'main':
text_buffer.c:54:8: warning: assignment makes integer from pointer without a cast [enabled by default]
ch = "";
^
text_buffer.c:18:7: warning: variable 'hasil' set but not used [-Wunused-but-set-variable]
int hasil;
^
text_buffer.c:17:8: warning: variable 'failed' set but not used [-Wunused-but-set-variable]
char failed;
^
CC common.o
CCLD text_buffer
I execute the program without error. This program will check input from user then run the sql command. The format of input shall be , e.g 123456,john doe then press enter. After 50-60 times of input, the double-linked list error will happen.
could anybody help why the error happen?
I am trying to write a code that will take two intergers, and will list all numbers lower than both of them except for those that are a factor of either if the two numbers inputted. At some point in my code though (see below) i am getting an error saying expected expression. I am a beginner so if you could explain this too me as simply as possible.
int main(int argc, const char * argv[])
{
#autoreleasepool {
int firstInterger;
int secondInterger;
int i;
printf("Please enter the first interger: ");
scanf("%i", &firstInterger);
printf("Please enter the second interger:");
scanf("%i", &secondInterger);
for (i = 0; i < firstInterger && i < secondInterger; i++) {
if ((firstInterger % i !== 0) && (secondInterger % i !== 0)) { //ERROR HERE!
printf("%i", i);
}
}
}
return 0;
}
You have twice the same error in that line.
You should replace !== with != or ==
const char *sentence = "He was not in the cab at the time.";
printf("\"%s\" has %d spaces\n", sentence, (int) ^ {
int i = 0;
int countSpaces = 0;
while (sentence[i] != '\0') {
if (sentence[i] == 0x20) {
countSpaces++;
}
i++;
}
return countSpaces;
});
This code simply counts the white space in a string, but for some reason it says 1606416608 spaces rather than 8. I'm not exactly sure what is going wrong, so thanks for any help!
You're passing the actual block to printf, not the result of the block. Instead, try
const char *sentence = "He was not in the cab at the time.";
printf("\"%s\" has %d spaces\n", sentence, (int) ^ {
int i = 0;
int countSpaces = 0;
while (sentence[i] != '\0') {
if (sentence[i] == 0x20) {
countSpaces++;
}
i++;
}
return countSpaces;
}()); // <-- note the extra parentheses here, indicating that you're calling the block
while doing a program related to variable argument function i
got the header file stdarg.h and have done some simple problem using it
but now when i a changing the actual argument's type it is showing some weird behaviour
here is my code:
#include<stdio.h>
#include<stdarg.h>
void fun(int a,...)
{
va_list k;
va_start(k,a);
int i=0;
printf("%d ",a);
while((i=va_arg(k,int)!=0)
{
printf(" %d ",i);
}
va_end(k);
}
int main()
{
fun(1,2,3,4,5,6);
printf("\n");
fflush(); //and without flush it is also showing some extra garbage value
fun(2,4,5);
printf("\n");
fflush();
fun('c','f','g','l');
return 0;
}
If you use the integer value 0 to indicate end of the argument list, you should also pass a 0 to fun.
fun(1,2,3,4,5,6,0);
fun(2,4,5,0);
First, end your list with 0, because you check for !=0 to detect the end. And also:
while((i=va_arg(k,int))!=0)
instead of
while(i=va_arg(k,int)!=0)
!= has higher precedence than =
This will give you the expected output:
1 2 3 4 5 6
Here's the complete code:
#include<stdio.h>
#include<stdarg.h>
void fun(int a,...)
{
va_list k;
va_start(k,a);
int i=0;
printf("%d ",a);
while((i=va_arg(k,int))!=0)
{
printf(" %d ",i);
}
va_end(k);
}
int main()
{
fun(1,2,3,4,5,6,0);
printf("\n");
//fun(2,4,5,0);
printf("\n");
//fun('c','f','g','l','\0');
getch();
return 0;
}