fpFlock
Lock a file (advisory lock)
Declaration
Source position: unix.pp line 125
function fpFlock(var T: text; mode: cint) : cint;
function fpFlock(var F: File; mode: cint) : cint;
function fpFlock(fd: cint; mode: cint) : cint;
Description
FpFLock implements file locking. it sets or removes a lock on the file F. F can be of type Text or File, or it can be a Linux file descriptor (a longint) Mode can be one of the following constants :
- LOCK_SH
- sets a shared lock.
- LOCK_EX
- sets an exclusive lock.
- LOCK_UN
- unlocks the file.
- LOCK_NB
- This can be OR-ed together with the other. If this is done the application doesn't block when locking.
The function returns zero if successful, a nonzero return value indicates an error.
Errors
Extended error information is returned by the FpGetErrno function:
See also
| Name | Description |
|---|---|
| FSync | Synchronize file's kernel data with disk. |
| #rtl.baseunix.FpFcntl | File control operations. |