FpFcntl

File control operations.

Declaration

Source position: line 0

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;

Read/set a file's attributes. Fildes a valid file descriptor. Cmd speciefies 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 siginificant 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.

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 \textbf{F_SetLk}, if the lock is held by another process.