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.