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Implementing file sharing

  figure224
Figure 9: File Sharing

Assume :
Only one process can have file open with write access
Permit multiple readers

If User Count = 0 and Write Flag = false then permit open in writemode

If Write Flag = false then permit open in readmode
Increment User Count

Require mutually exclusive access to whole Open File table or individual entries in table, but access only required for short time



Omer F Rana
Sat Feb 15 19:06:41 GMT 1997