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/*-------------------------------------------------------------------------
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* Virtual file descriptor definitions.
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* Portions Copyright (c) 1996-2009, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*-------------------------------------------------------------------------
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* File {Close, Read, Write, Seek, Tell, Sync}
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* {File Name Open, Allocate, Free} File
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* These are NOT JUST RENAMINGS OF THE UNIX ROUTINES.
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* Use them for all file activity...
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* fd = FilePathOpenFile("foo", O_RDONLY, 0600);
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* Use AllocateFile, not fopen, if you need a stdio file (FILE*); then
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* use FreeFile, not fclose, to close it. AVOID using stdio for files
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* that you intend to hold open for any length of time, since there is
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* no way for them to share kernel file descriptors with other files.
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* Likewise, use AllocateDir/FreeDir, not opendir/closedir, to allocate
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* open directories (DIR*).
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* FileSeek uses the standard UNIX lseek(2) flags.
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typedef char *FileName;
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extern int max_files_per_process;
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* prototypes for functions in fd.c
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/* Operations on virtual Files --- equivalent to Unix kernel file ops */
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extern File PathNameOpenFile(FileName fileName, int fileFlags, int fileMode);
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extern File OpenTemporaryFile(bool interXact);
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extern void FileClose(File file);
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extern int FilePrefetch(File file, off_t offset, int amount);
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extern int FileRead(File file, char *buffer, int amount);
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extern int FileWrite(File file, char *buffer, int amount);
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extern int FileSync(File file);
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extern off_t FileSeek(File file, off_t offset, int whence);
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extern int FileTruncate(File file, off_t offset);
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/* Operations that allow use of regular stdio --- USE WITH CAUTION */
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extern FILE *AllocateFile(const char *name, const char *mode);
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extern int FreeFile(FILE *file);
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/* Operations to allow use of the <dirent.h> library routines */
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extern DIR *AllocateDir(const char *dirname);
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extern struct dirent *ReadDir(DIR *dir, const char *dirname);
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extern int FreeDir(DIR *dir);
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/* If you've really really gotta have a plain kernel FD, use this */
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extern int BasicOpenFile(FileName fileName, int fileFlags, int fileMode);
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/* Miscellaneous support routines */
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extern void InitFileAccess(void);
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extern void set_max_safe_fds(void);
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extern void closeAllVfds(void);
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extern void SetTempTablespaces(Oid *tableSpaces, int numSpaces);
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extern bool TempTablespacesAreSet(void);
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extern Oid GetNextTempTableSpace(void);
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extern void AtEOXact_Files(void);
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extern void AtEOSubXact_Files(bool isCommit, SubTransactionId mySubid,
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SubTransactionId parentSubid);
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extern void RemovePgTempFiles(void);
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extern int pg_fsync(int fd);
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extern int pg_fsync_no_writethrough(int fd);
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extern int pg_fsync_writethrough(int fd);
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extern int pg_fdatasync(int fd);
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/* Filename components for OpenTemporaryFile */
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#define PG_TEMP_FILES_DIR "pgsql_tmp"
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#define PG_TEMP_FILE_PREFIX "pgsql_tmp"