Interested to Buy Any Domain ? << Click Here >> for more details...
what is the difference between. system call and library
function?
- 2 Answers
- 20468 Views
- CDAC, Satyam, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
system calls are provided by the system and are executed in
the system kernel. They are entry points into the kernel and
are therefore NOT linked into your program. These are not
portable calls.
ยท Library calls include the ANSI C standard library and
are therefore portable. These functions are linked into your
program.
It is worth noting that, because system calls are part of
the O/S. The program has to make a context switch to the
kernel when they are called and because of this, they have a
high startup overhead. The upside is that the time executing
these routines is assigned to the OS and not the user program.
| Is This Answer Correct ? | 66 Yes | 9 No |
Answer / eng abedalmohdi almomani
system call can be called from either kernel space or user
space(in this case include switch to privilage mode) and
executed in kernel space while library called only from
user programm and may call systemcall to perform it is
function like "printf" that need "write" system call while
other not need kernel at all like sin(),cos().....
systemcall examples : write,read,close,mmap,open,.......
library examples: fopen,fclose,printf,scanf,fscanf,.....
| Is This Answer Correct ? | 38 Yes | 8 No |
Do you know the purpose of 'register' keyword?
What is the value of a[3] if integer a[] = {5,4,3,2,1}?
What are the advantages of using Unions?
How to implement variable argument functions ?
Difference between pass by reference and pass by value?
Define a structure to store the record of library. The record must consist of at least following fields: Title, Author, Edition, Price, Publisher, and Category. -Define functions authorSearch ( ), TitleSearch ( ) and CategorySearch ( ) to search a book with respect to author, title and category. [There can be more than one book, written by one author, in one category]
What does it mean when the linker says that _end is undefined?
a.One Cannot Take the address of a Bit Field b.bit fields cannot be arrayed c.Bit-Fields are machine Dependant d.Bit-fields cannot be declared as static Which of the Following Statements are true w.r.t Bit-Fields A)a,b&c B)Only a & b C)Only c D)All
3 Answers Accenture, Digg.com,
C program to perform stack operation using singly linked list
Explain how can you check to see whether a symbol is defined?
What is the use of bit field?
How to add two numbers with using function?
C 
