FpFcntl

File control operations.

Declaration

Source position: bunxh.inc line 58

  function FpFcntl(fildes: cint; cmd: cint) : cint;
  function FpFcntl(fildes: cint; cmd: cint; arg: cint) : cint;
  function FpFcntl(fildes: cint; cmd: cint; var arg: FLock) : cint;

Description

Read/set a file's attributes. Fildes a valid file descriptor. Cmd specifies what to do, and is one of the following:

F_GetFd

Read the close_on_exec flag. If the low-order bit is 0, then the file will remain open across execve calls.

F_GetFl

Read the descriptor's flags.

F_GetOwn

Get the Process ID of the owner of a socket.

F_SetFd

Set the close_on_exec flag of fildes. (only the least significant bit is used).

F_GetLk

Return the flock record that prevents this process from obtaining the lock, or set the l_type field of the lock of there is no obstruction. Arg is the flock record.

F_SetLk

Set the lock or clear it (depending on l_type in the flock structure). if the lock is held by another process, an error occurs.

F_GetLkw

Same as for F_Setlk, but wait until the lock is released.

F_SetOwn

Set the Process or process group that owns a socket.

The function returns 0 if successful, -1 otherwise.

Errors

On error, -1 is returned. Use fpGetErrno for extended error information.

sys_ebadf

Fd has a bad file descriptor.

sys_eagain or sys_eaccess

For ****, if the lock is held by another process.