[Overview][Constants][Types][Procedures and functions][Variables][Index] | Reference for unit 'oldlinux' (#rtl)

# Flock

Lock a file (advisory lock)

## Declaration

Source position: line 0

`function Flock(`
`fd: LongInt;`
`mode: LongInt`
`):Boolean; function Flock(`
`var T: text;`
`mode: LongInt`
`):Boolean; function Flock(`
`var F: file;`
`mode: LongInt`
`):Boolean;`

## Description

FLock 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 filedescriptor (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 True if successful, False otherwise.

## Errors

If an error occurs, it is reported in LinuxError.

## See also

Fcntl |  | File control operations.

Documentation generated on: Feb 26 2014