c - How to ensure that when my process is operating on a file, no other process tries to write to it or delete it? -

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if process trying read file, how ensure code (c language) no other process either writes or deletes (include system commands deleting file)?

also, can achieved on os (windows, linux, solaris, hp-ux, vxworks etc)?

edit: i'll answer unix/linux

as gspr , others said, take @ file locking using fcntl, flock, etc. however, warned advisory locking methods.

what mean? means can warn other processes accesing file, or portion of it, you can't forcibly keep them ignoring , writing on file.

there no compulsory locking primitives. can use permissions advantage, you'll never have full guarantees -- root user can override limitations. don't think there's way work around that.


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