What is a semaphore?
- 20 Answers
- 50091 Views
- Motorola, Persistent, TCS, I also Faced
- E-Mail Answers
Answers were Sorted based on User's Feedback
Answer / dibya jyoti(titanmtp)
Semaphore is a technique in which we can avoid the mutual
exclusion problem.or in other words we say it as the
protected variable(ie.They are used for process sync and
are used to resolve deadlock conditions.)
That means if there are many proceess sharing
a same resources then other process must wait it until the
process in critical section is completed as the process in
critical section is completed its send a signal to the
other process to enter a critical section.
basically it is done in two types
1*General semaphore or (counting semaphore)
2*Binary semaphore or (Mutex)
| Is This Answer Correct ? | 2 Yes | 2 No |
Answer / aditya singh
In programming, especially in Unix systems, semaphores are a
technique for coordinating or synchronizing activities in
which multiple processes compete for the same operating
system resources. A semaphore is a value in a designated
place in operating system (or kernel) storage that each
process can check and then change. Depending on the value
that is found, the process can use the resource or will find
that it is already in use and must wait for some period
before trying again. Semaphores can be binary (0 or 1) or
can have additional values. Typically, a process using
semaphores checks the value and then, if it using the
resource, changes the value to reflect this so that
subsequent semaphore users will know to wait.
Semaphores are commonly use for two purposes: to share a
common memory space and to share access to files. Semaphores
are one of the techniques for interprocess communication
(IPC). The C programming language provides a set of
interfaces or "functions" for managing semaphores.
| Is This Answer Correct ? | 1 Yes | 1 No |
Answer / sri
In programming, especially in Unix systems, semaphores are a
technique for coordinating or synchronizing activities in
which multiple processes compete for the same operating
system resources. A semaphore is a value in a designated
place in operating system (or kernel) storage that each
process can check and then change. Depending on the value
that is found, the process can use the resource or will find
that it is already in use and must wait for some period
before trying again. Semaphores can be binary (0 or 1) or
can have additional values. Typically, a process using
semaphores checks the value and then, if it using the
resource, changes the value to reflect this so that
subsequent semaphore users will know to wait.
Semaphores are commonly use for two purposes: to share a
common memory space and to share access to files. Semaphores
are one of the techniques for interprocess communication
(IPC). The C programming language provides a set of
interfaces or "functions" for managing semaphores.
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / priya
Semaphore is a Variable or abstract data type that provide a simple but useful abstraction for controlling access by multiple processes to common resourse in a parallel programming or multiuser environment.
semaphore is as a record of how many units of a perticular resources are available.
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / alladiya qureshi
it is the share global variable,it can be implemented as
integer or a structure and this semaphore variable will be
used for synchronization.there are two function used to
excess the value of semaphore variable -
1.wait semaphore
2.signal semaphore
| Is This Answer Correct ? | 0 Yes | 0 No |
Answer / muthukumar
semaphore is mutual execution problem presented in the last
section are not easy to more complex problems.
Semaphore is a Only Non Negative integer variable.
semaphore initialized value in 1.
Semaphore only Through Two Standard atomic Operation
P(wait)
s=s-1
and
V(signal)
s=s+1
| Is This Answer Correct ? | 4 Yes | 5 No |
Answer / omkar singh
A semaphore s is an integer value that apart from initialization accessd only through the two standard opereation wait() and signal(). A semaphore s played an important role where shared resources are used. the main objective of the semaphore is to maintain mutual exclusion and provide a solution for critical section problem.
| Is This Answer Correct ? | 0 Yes | 1 No |
Answer / addy thompson
semaphore is set of rules of SEX...
it derived from the Latin word SEXAPHORE which means doing sex with multiple person.
thank you
for more inquiry please add me on facebook
my id is "bestattitude007@gmail.com"
| Is This Answer Correct ? | 2 Yes | 5 No |
Answer / rupam quila
The semaphore abstract data type is perhaps the simplest
universally useful implementation of the variables uses as
arguments to the wait and signal operations although there
are many implementations of semaphores, they can be
intuitively thought of as integers, where wait(x) or the
object-orinted x.wait waits until x is greater then zero
and then decrements it, and signal(x)or x.signal increments
x.
| Is This Answer Correct ? | 5 Yes | 16 No |
Can you just explain about memory management in iOS?
Will disk cleanup delete my files?
What causes a computer not to boot up?
Why does kernel panic occur?
What are compile time Errors?
0 Answers Akamai Technologies, Impetus, iNautix,
In the process table entry for the kernel process, the process id value is a) 0 b) 1 c) 2 d) 255 e) it does not have a process table entry
4 Answers Aspire, IBM, Saigun Technologies,
How can I increase storage on my laptop?
Can I delete old updates to free up disk space?
How do you find out computer specs?
What is the difference between wget and curl?
What is a file in computer terms?
what is gr-edge edit?
Windows 
