How to use sprintf instead of hardcoded values

Posted by astha goyal on Stack Overflow See other posts from Stack Overflow or by astha goyal
Published on 2010-03-20T10:52:14Z Indexed on 2010/03/20 11:21 UTC
Read the original article Hit count: 440

Filed under:

c

|

printf

|

beginner

I am developing a firewall for Linux as my project. I am able to capture packets and to block them. I am using IPTABLES.

How can I use variables with sprintf instead of hardcoded values?

sprintf(comm, "iptables -A INPUT -s $str -j DROP")
// inplace of:
sprintf(comm, "iptables -A INPUT -s 192.168.0.43 -j DROP")

Related posts about printf

C Number to Text problem with ones and tens..

as seen on Stack Overflow - Search for 'Stack Overflow'
#include<stdio.h> #include<conio.h> main() { int ones,tens,ventoteen, myloop = 0; long num2,cents2,centeens,cents1,thousands,hundreds; double num; do{ printf("Enter a number: "); scanf("%lf",&num); if(num<=10000 || num>=0) { if (num==0) { printf("\t\tZero"); } num=(num*100); num2=… >>> More
Avoid trailing zeroes in printf()

as seen on Stack Overflow - Search for 'Stack Overflow'
I keep stumbling on the format specifiers for the printf() family of functions. What I want is to be able to print a double (or float) with a maximum given number of digits after the decimal point. If I use: printf("%1.3f", 359.01335); printf("%1.3f", 359.00999); I get 359.013 359.010 Instead… >>> More
How to get colored output with printf?

as seen on Stack Overflow - Search for 'Stack Overflow'
Hello, is there a way to get with printf colored output? #!/usr/bin/perl use warnings; use strict; use Term::ANSIColor; printf "%4.4s\n", colored( '0123456789', 'magenta' ); Output: (only newline) >>> More
Unexpected result from printf

as seen on Stack Overflow - Search for 'Stack Overflow'
#include<stdio.h> int main() { printf("He %c llo",65); } Output: He A llo #include<stdio.h> int main() { printf("He %c llo",13); } Output: llo. It doesnt print He. I can understand that 65 is ascii value for A and hence A is printed in first case but why llo in second case… >>> More
printing reverse in singly link list using pointers

as seen on Stack Overflow - Search for 'Stack Overflow'
i have been trying this code. i think the logic is ok but the program terminates abruptly when the display_rev function is called here is code of display_rev void display_rev(emp_node *head) { emp_node *p=head, *q; while(p->next != NULL) p=p->next; while(p!=head || p==head){ … >>> More

Developer IT

How to use sprintf instead of hardcoded values - Developer IT

How to use sprintf instead of hardcoded values

c

printf

beginner

Related posts about c

Related posts about printf

C Number to Text problem with ones and tens..

Avoid trailing zeroes in printf()

How to get colored output with printf?

Unexpected result from printf

printing reverse in singly link list using pointers

Categories cloud