Golgappa.net | Golgappa.org | BagIndia.net | BodyIndia.Com | CabIndia.net | CarsBikes.net | CarsBikes.org | CashIndia.net | ConsumerIndia.net | CookingIndia.net | DataIndia.net | DealIndia.net | EmailIndia.net | FirstTablet.com | FirstTourist.com | ForsaleIndia.net | IndiaBody.Com | IndiaCab.net | IndiaCash.net | IndiaModel.net | KidForum.net | OfficeIndia.net | PaysIndia.com | RestaurantIndia.net | RestaurantsIndia.net | SaleForum.net | SellForum.net | SoldIndia.com | StarIndia.net | TomatoCab.com | TomatoCabs.com | TownIndia.com
Interested to Buy Any Domain ? << Click Here >> for more details...


how do you redirect stdout value from a program to a file?



how do you redirect stdout value from a program to a file?..

Answer / ataraxic

int main(int argc, char *argv[], char *envp[])
{
char *p;
int fd = open("/tmp/mydata", O_CREAT|O_WRONLY);

if ( fd < 0 ) {
perror("open");
return -1;
}

/*

* close(2) system call deletes a descriptor from
* the per-process object reference table. In the
* per-process object reference table, stdin,
* stdout,stderr were placed at positions 0,1,2
* respectively.
*/

close(1);
/*
* Place our file descriptor at the place of stdout.
* Read man dup(2).
*/

dup(fd);

/*
* printf(3) is ultimately calling write(2) with
* first argument as 1
*/



printf("Hello there!\n");
p = getenv("MDEV");
if (p != NULL)
printf("MDEV is: %s\n", p);

p = getenv("SUBSYSTEM");
if (p != NULL)
printf("SUBSYSTEM is: %s\n", p);

return 0;

}

Is This Answer Correct ?    1 Yes 0 No

Post New Answer

More C Interview Questions

What is hungarian notation? Is it worthwhile?

0 Answers  


Write a Program to find whether the given number or string is palindrome.

0 Answers   InterGraph,


What are predefined functions in c?

0 Answers  


c program to subtract between two numbers without using '-' sign and subtract function.

1 Answers  


How are structure passing and returning implemented?

0 Answers  


write a program that reads lines(using getline), converts each line to an integer using atoi, and computes the average of all the numbers read. also compute the standard deviation.

0 Answers  


wt is d full form of c

6 Answers   TCS, Wipro,


int main() { int i=1; switch(i) { case '1': printf("hello"); break; case 1: printf("Hi"); break; case 49: printf("Good Morning"); break; } return 0; }

3 Answers  


What are the types of variables in c?

0 Answers  


What are the types of pointers?

0 Answers  


do you think its fraud or original company?

0 Answers  


how to make c program without a libary? e.g.#include<stdio.h> libary is not in c progaram.

2 Answers  


Categories