Linux Search Pattern Question:
Download Questions PDF

Do you know what is the output of this program?

#include<stdio.h>
#include<fcntl.h>

int main()
{
int fd, count;
fd = open("google.txt",O_WRONLY|O_CREAT);
count = write(fd,"Linux System Programming",5);
if(count != 5)
perror("write");
return 0;
}
a) it will create a file "google.txt" in the present working directory
b) it will write the string "Linux System Programming" in the file "google.txt"
c) both (a) and (b)
d) none of the mentioned

Answer:

a) it will create a file "google.txt" in the present working directory
Explanation:
This program will write only "Linux" in the file "google.txt" because we are writing only 5 bytes with "write" system call.
Output:
[root@localhost google]# gcc -o san san.c
[root@localhost google]# ls
san san.c
[root@localhost google]# ./san
[root@localhost google]# ls
san san.c google.txt
[root@localhost google]# vim google.txt
[root@localhost google]#

Download Search Pattern Interview Questions And Answers PDF

Previous QuestionNext Question
What is the output of this program?

#include<stdio.h>
#include<fcntl.h>

int main()
{
int fd, count;
fd = open("san.c",O_RDONLY);
count = write(fd,"Linux",5);
if(count != 5)
perror("write");
return 0;
}
a) it will write the string "Linux" in the beginning of source file "san.c"
b) it will write the string "Linux" in the end of the source file "san.c"
c) segmentation fault
d) none of the mentioned
Output of this program?

#include<stdio.h>
#include<fcntl.h>

int main()
{
pid_t fd;
char ch;
int count;
fd = open("san.c",O_RDONLY);
do{
count = read(fd,&ch,1);
printf("%c",ch);
}while(count);
return 0;
}
a) it will print nothing
b) it will print the source code of the source file "san.c"
c) segmentation fault
d) none of the mentioned