Name
flock
- flock
options fileId
[start
] [length
] [origin
] Place a lock on all or part of the file open with identifier
fileId
. The file data is locked from the beginning of byte offsetstart
for a length oflength
bytes. The default start position is the start of file, and the default length is to the end of file. If the file is currently locked, the command waits until it is unlocked before returning.The value of
origin
indicates the offset for the data locked and is one of the stringsstart
(relative to start of file, the default),current
(relative to the current access position), orend
(relative to end of file, extending backward).This command is not supported on Windows 95/98. Also see funlock.
Options
- -read
Place a read lock on the file.
- -write
Place a write lock on the file.
- -nowait
Do not block if lock cannot be obtained. Return 1 if the file could be locked, or 0 if it could not.
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