文件打开的常量
以下常量旨在与 fs.open() 一起使用。
The following constants are meant for use with fs.open().
| Constant | Description |
|---|---|
O_RDONLY |
Flag indicating to open a file for read-only access. |
O_WRONLY |
Flag indicating to open a file for write-only access. |
O_RDWR |
Flag indicating to open a file for read-write access. |
O_CREAT |
Flag indicating to create the file if it does not already exist. |
O_EXCL |
Flag indicating that opening a file should fail if the
O_CREAT flag is set and the file already exists. |
O_NOCTTY |
Flag indicating that if path identifies a terminal device, opening the path shall not cause that terminal to become the controlling terminal for the process (if the process does not already have one). |
O_TRUNC |
Flag indicating that if the file exists and is a regular file, and the file is opened successfully for write access, its length shall be truncated to zero. |
O_APPEND |
Flag indicating that data will be appended to the end of the file. |
O_DIRECTORY |
Flag indicating that the open should fail if the path is not a directory. |
O_NOATIME |
Flag indicating reading accesses to the file system will no longer
result in an update to the atime information associated with
the file. This flag is available on Linux operating systems only. |
O_NOFOLLOW |
Flag indicating that the open should fail if the path is a symbolic link. |
O_SYNC |
Flag indicating that the file is opened for synchronized I/O with write operations waiting for file integrity. |
O_DSYNC |
Flag indicating that the file is opened for synchronized I/O with write operations waiting for data integrity. |
O_SYMLINK |
Flag indicating to open the symbolic link itself rather than the resource it is pointing to. |
O_DIRECT |
When set, an attempt will be made to minimize caching effects of file I/O. |
O_NONBLOCK |
Flag indicating to open the file in nonblocking mode when possible. |
UV_FS_O_FILEMAP |
When set, a memory file mapping is used to access the file. This flag is available on Windows operating systems only. On other operating systems, this flag is ignored. |
On Windows, only O_APPEND, O_CREAT, O_EXCL, O_RDONLY, O_RDWR,
O_TRUNC, O_WRONLY, and UV_FS_O_FILEMAP are available.
