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semaphores

13
Hi to all,

can anybody explain about semaphores?

i want exact definition of semaphore?

i have searched somany books but i could not get it?

whre and how they can be used?

plz help me on this.........
Jan 21 '07 #1
4 2733
Loismustdie129
195 100+
What you need to do is you need to search for them on google or wikipedia. I mean I didn't know a thing about semaphores and I went to look them up and found many useful items.
Jan 21 '07 #2
Motoma
3,237 Expert 2GB
Hi to all,

can anybody explain about semaphores?

i want exact definition of semaphore?

i have searched somany books but i could not get it?

whre and how they can be used?

plz help me on this.........
In Google, type "define:semaphore"
Jan 23 '07 #3
horace1
1,510 Expert 1GB
Hi to all,

can anybody explain about semaphores?

i want exact definition of semaphore?

i have searched somany books but i could not get it?

whre and how they can be used?

plz help me on this.........
have a look at the section on IPC: Semaphores in
http://www.cs.cf.ac.uk/Dave/C/
Jan 30 '07 #4
Hi to all,

can anybody explain about semaphores?

i want exact definition of semaphore?

i have searched somany books but i could not get it?

whre and how they can be used?

plz help me on this.........

Hi,

semaphore is just like a token.

for ex: if u book a ticket in flight to travel to some xxx place on monday 10.00 am that place is booked for u untill u reach the dest nobody will ask u to get out.
but if u come on tuesday for that same flighr and argur that i have booked the ticket its not valid.

this is wat semaphore is:
its a protected variable. when a process acquires a semaphore it has the fulll control over the entire cpu and if other proces have to execute they have to wait for the completion of the process which is presently holding the semaphore variable.
after its completion only its releases the semaphore so that the other process can acquire it to finish its work or routine.
Oct 24 '07 #5

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