While using fork(), child shares parent address space , Correct me If I am wrong ..
On Fri, Jun 3, 2011 at 10:28 PM, nitish goyal <[email protected]> wrote: > Hi all, > > I am stuck with this code..Can anyone tell me how to implement semaphores in > fork system call > Code: > > #include<stdio.h> > > int signal(int *n); > int wait(int *n); > > > int main() > { > int n; > n=0; > if(fork()) > { > printf("Hello"); > signal(&n); > } > else > { > wait(&n); > printf("World"); > } > } > int signal(int *n) > { > (*n)++; > } > int wait(int *n) > { > while((*n)<=0); > (*n)--; > } > > Since parent process and child process will be having different address > spaces...so change of n in one address space will not be visible to other.so > please tell me how to make n visible to both the processes > > On Fri, Jun 3, 2011 at 2:45 PM, Subhransu <[email protected]> > wrote: >> >> Here you go in C code >> http://codepad.org/gk6AZj0T >> >> >> int main() >> { >> if(printf("hello")!=0) { >> printf("world"); >> } >> else { >> printf("SCREWED ! ! !"); } >> >> return 0; >> } >> >> >> Subhransu Panigrahi >> >> Mobile: +91-9840931538 >> Email: [email protected] >> >> >> On Fri, Jun 3, 2011 at 1:57 PM, Naveen Kumar <[email protected]> >> wrote: >>> >>> Hi Shachindra, >>> I don't think letters will be jumbled because we a calling one api to >>> output on console & tty's driver takes whole line and output it at once. >>> >>> On Fri, Jun 3, 2011 at 12:40 PM, Vishal Thanki <[email protected]> >>> wrote: >>>> >>>> @sachindra, @naveen, >>>> this was just a plain trick to execute "if" and "else" block. i agree >>>> with your concerns :) >>>> >>>> 2011/6/3 Vιиodh <[email protected]>: >>>> > @vishal: >>>> > can u explain the fork() solution?? >>>> > >>>> > On Fri, Jun 3, 2011 at 12:16 PM, Shachindra A C >>>> > <[email protected]> >>>> > wrote: >>>> >> >>>> >> There can be some synchronisation problems with fork() right? say >>>> >> world >>>> >> might get printed first...or maybe the letters can get jumbled >>>> >> too...We >>>> >> cannot guarantee the order of execution unless we use semaphores. >>>> >> >>>> >> On Fri, Jun 3, 2011 at 12:14 PM, Naveen Kumar >>>> >> <[email protected]> >>>> >> wrote: >>>> >>> >>>> >>> oh yes, >>>> >>> gud one >>>> >>> >>>> >>> On Fri, Jun 3, 2011 at 12:12 PM, Vishal Thanki >>>> >>> <[email protected]> >>>> >>> wrote: >>>> >>>> >>>> >>>> vishal@ubuntu:~/progs/c\ 12:11:53 PM >$ cat fork.c >>>> >>>> #include <stdio.h> >>>> >>>> #include <stdlib.h> >>>> >>>> >>>> >>>> int main() >>>> >>>> { >>>> >>>> if (fork()) { >>>> >>>> printf("hello "); >>>> >>>> } else { >>>> >>>> printf("world\n"); >>>> >>>> } >>>> >>>> return 0; >>>> >>>> } >>>> >>>> vishal@ubuntu:~/progs/c\ 12:11:56 PM >$ gcc fork.c >>>> >>>> vishal@ubuntu:~/progs/c\ 12:12:06 PM >$ ./a.out >>>> >>>> hello world >>>> >>>> >>>> >>>> >>>> >>>> On Fri, Jun 3, 2011 at 12:09 PM, Naveen Kumar >>>> >>>> <[email protected]> wrote: >>>> >>>> > Hi Vishal, >>>> >>>> > >>>> >>>> > Can you show us how it be done with fork? >>>> >>>> > >>>> >>>> > On Fri, Jun 3, 2011 at 12:02 PM, Vishal Thanki >>>> >>>> > <[email protected]> >>>> >>>> > wrote: >>>> >>>> >> >>>> >>>> >> can use fork() also.. >>>> >>>> >> >>>> >>>> >> On Fri, Jun 3, 2011 at 11:57 AM, anand karthik >>>> >>>> >> <[email protected]> wrote: >>>> >>>> >> > (!printf("Hello")) >>>> >>>> >> > >>>> >>>> >> > On Jun 3, 2011 11:52 AM, "Arpit Mittal" >>>> >>>> >> > <[email protected]> >>>> >>>> >> > wrote: >>>> >>>> >> >> Please help me in this question. >>>> >>>> >> >> >>>> >>>> >> >> What's the "condition" so that the following code prints both >>>> >>>> >> >> HelloWorld ! >>>> >>>> >> >> >>>> >>>> >> >> if "condition" >>>> >>>> >> >> printf ("Hello"); >>>> >>>> >> >> else >>>> >>>> >> >> printf("World"); >>>> >>>> >> >> >>>> >>>> >> >> >>>> >>>> >> >> >>>> >>>> >> >> >>>> >>>> >> >> -- >>>> >>>> >> >> -Arpit Mittal >>>> >>>> >> >> 6th Semester, >>>> >>>> >> >> Indian Institute of Information Technology,Allahabad >>>> >>>> >> >> Email : [email protected] >>>> >>>> >> >> [email protected] >>>> >>>> >> >> Contact : +91-8853049787 >>>> >>>> >> >> >>>> >>>> >> >> Let every man be respected as an individual and no man >>>> >>>> >> >> idolized. >>>> >>>> >> >> >>>> >>>> >> >> -- >>>> >>>> >> >> You received this message because you are subscribed to the >>>> >>>> >> >> Google >>>> >>>> >> >> Groups >>>> >>>> >> >> "Algorithm Geeks" group. >>>> >>>> >> >> To post to this group, send email to >>>> >>>> >> >> [email protected]. >>>> >>>> >> >> To unsubscribe from this group, send email to >>>> >>>> >> >> [email protected]. >>>> >>>> >> >> For more options, visit this group at >>>> >>>> >> >> http://groups.google.com/group/algogeeks?hl=en. >>>> >>>> >> >> >>>> >>>> >> > >>>> >>>> >> > -- >>>> >>>> >> > You received this message because you are subscribed to the >>>> >>>> >> > Google >>>> >>>> >> > Groups >>>> >>>> >> > "Algorithm Geeks" group. >>>> >>>> >> > To post to this group, send email to >>>> >>>> >> > [email protected]. >>>> >>>> >> > To unsubscribe from this group, send email to >>>> >>>> >> > [email protected]. >>>> >>>> >> > For more options, visit this group at >>>> >>>> >> > http://groups.google.com/group/algogeeks?hl=en. >>>> >>>> >> > >>>> >>>> >> >>>> >>>> >> -- >>>> >>>> >> You received this message because you are subscribed to the >>>> >>>> >> Google >>>> >>>> >> Groups >>>> >>>> >> "Algorithm Geeks" group. >>>> >>>> >> To post to this group, send email to [email protected]. >>>> >>>> >> To unsubscribe from this group, send email to >>>> >>>> >> [email protected]. >>>> >>>> >> For more options, visit this group at >>>> >>>> >> http://groups.google.com/group/algogeeks?hl=en. >>>> >>>> >> >>>> >>>> > >>>> >>>> > >>>> >>>> > >>>> >>>> > -- >>>> >>>> > Cheers >>>> >>>> > Naveen Kumar >>>> >>>> > >>>> >>>> > -- >>>> >>>> > You received this message because you are subscribed to the >>>> >>>> > Google >>>> >>>> > Groups >>>> >>>> > "Algorithm Geeks" group. >>>> >>>> > To post to this group, send email to [email protected]. >>>> >>>> > To unsubscribe from this group, send email to >>>> >>>> > [email protected]. >>>> >>>> > For more options, visit this group at >>>> >>>> > http://groups.google.com/group/algogeeks?hl=en. >>>> >>>> > >>>> >>>> >>>> >>>> -- >>>> >>>> You received this message because you are subscribed to the Google >>>> >>>> Groups "Algorithm Geeks" group. >>>> >>>> To post to this group, send email to [email protected]. >>>> >>>> To unsubscribe from this group, send email to >>>> >>>> [email protected]. >>>> >>>> For more options, visit this group at >>>> >>>> http://groups.google.com/group/algogeeks?hl=en. >>>> >>>> >>>> >>> >>>> >>> >>>> >>> >>>> >>> -- >>>> >>> Cheers >>>> >>> Naveen Kumar >>>> >>> >>>> >>> -- >>>> >>> You received this message because you are subscribed to the Google >>>> >>> Groups >>>> >>> "Algorithm Geeks" group. >>>> >>> To post to this group, send email to [email protected]. >>>> >>> To unsubscribe from this group, send email to >>>> >>> [email protected]. >>>> >>> For more options, visit this group at >>>> >>> http://groups.google.com/group/algogeeks?hl=en. >>>> >> >>>> >> >>>> >> >>>> >> -- >>>> >> Regards, >>>> >> Shachindra A C >>>> >> >>>> >> -- >>>> >> You received this message because you are subscribed to the Google >>>> >> Groups >>>> >> "Algorithm Geeks" group. >>>> >> To post to this group, send email to [email protected]. >>>> >> To unsubscribe from this group, send email to >>>> >> [email protected]. >>>> >> For more options, visit this group at >>>> >> http://groups.google.com/group/algogeeks?hl=en. >>>> > >>>> > >>>> > >>>> > -- >>>> > With regards, >>>> > Vιиodh >>>> > >>>> > -- >>>> > You received this message because you are subscribed to the Google >>>> > Groups >>>> > "Algorithm Geeks" group. >>>> > To post to this group, send email to [email protected]. >>>> > To unsubscribe from this group, send email to >>>> > [email protected]. >>>> > For more options, visit this group at >>>> > http://groups.google.com/group/algogeeks?hl=en. >>>> > >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Algorithm Geeks" group. >>>> To post to this group, send email to [email protected]. >>>> To unsubscribe from this group, send email to >>>> [email protected]. >>>> For more options, visit this group at >>>> http://groups.google.com/group/algogeeks?hl=en. >>>> >>> >>> >>> >>> -- >>> Cheers >>> Naveen Kumar >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "Algorithm Geeks" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]. >>> For more options, visit this group at >>> http://groups.google.com/group/algogeeks?hl=en. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Algorithm Geeks" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]. >> For more options, visit this group at >> http://groups.google.com/group/algogeeks?hl=en. > > > > -- > Regards, > Nitish Goyal > Undergraduate Student Of NSIT, > Computer Engineering (B.E.) > Asst. PlaceComm 2011 > contact me:- +91-9999605824 > Reply at :- [email protected] > > -- > You received this message because you are subscribed to the Google Groups > "Algorithm Geeks" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/algogeeks?hl=en. > -- Lalit Kishore Sharma, IIIT Allahabad (Amethi Capmus), 6th Sem. -- You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/algogeeks?hl=en.
