Week 03 Lectures (33)

File Descriptor Pool (cont)

Interface to file descriptor (pool):

File PathNameOpenFile(char *fileName, int flags)
      // open a file with default pg.conf mode
File PathNameOpenFilePerm(char *fName, int flags, int mode)
     // open a file in the DB directory ($PGDATA/base/...)
File OpenTemporaryFile(bool interXact)
     // open temp file flag: close at end of transaction?
void FileClose(File file)
void FileUnlink(File file)
int  FileRead(File file, char *buffer, int amount)
int  FileWrite(File file, char *buffer, int amount)
int  FileSync(File file)
long FileSeek(File file, long offset, int whence)
int  FileTruncate(File file, long offset)

Analogous to Unix syscalls open(), close(), read(), ...