File I/O Handling Functions

Modules
	File Open Flags/Routines
	File Seek Flags
	File Attribute Flags
	{_full} max iovec size
	File Lock Types
Typedefs
typedef apr_uint32_t	apr_fileattrs_t
typedef int	apr_seek_where_t
typedef struct apr_file_t	apr_file_t
Functions
apr_status_t	apr_file_open (apr_file_t **newf, const char *fname, apr_int32_t flag, apr_fileperms_t perm, apr_pool_t *pool)
apr_status_t	apr_file_close (apr_file_t *file)
apr_status_t	apr_file_remove (const char *path, apr_pool_t *pool)
apr_status_t	apr_file_rename (const char *from_path, const char *to_path, apr_pool_t *pool)
apr_status_t	apr_file_link (const char *from_path, const char *to_path)
apr_status_t	apr_file_copy (const char *from_path, const char *to_path, apr_fileperms_t perms, apr_pool_t *pool)
apr_status_t	apr_file_append (const char *from_path, const char *to_path, apr_fileperms_t perms, apr_pool_t *pool)
apr_status_t	apr_file_eof (apr_file_t *fptr)
apr_status_t	apr_file_open_stderr (apr_file_t **thefile, apr_pool_t *pool)
apr_status_t	apr_file_open_stdout (apr_file_t **thefile, apr_pool_t *pool)
apr_status_t	apr_file_open_stdin (apr_file_t **thefile, apr_pool_t *pool)
apr_status_t	apr_file_open_flags_stderr (apr_file_t **thefile, apr_int32_t flags, apr_pool_t *pool)
apr_status_t	apr_file_open_flags_stdout (apr_file_t **thefile, apr_int32_t flags, apr_pool_t *pool)
apr_status_t	apr_file_open_flags_stdin (apr_file_t **thefile, apr_int32_t flags, apr_pool_t *pool)
apr_status_t	apr_file_read (apr_file_t *thefile, void *buf, apr_size_t *nbytes)
apr_status_t	apr_file_write (apr_file_t *thefile, const void *buf, apr_size_t *nbytes)
apr_status_t	apr_file_writev (apr_file_t *thefile, const struct iovec *vec, apr_size_t nvec, apr_size_t *nbytes)
apr_status_t	apr_file_read_full (apr_file_t *thefile, void *buf, apr_size_t nbytes, apr_size_t *bytes_read)
apr_status_t	apr_file_write_full (apr_file_t *thefile, const void *buf, apr_size_t nbytes, apr_size_t *bytes_written)
apr_status_t	apr_file_writev_full (apr_file_t *thefile, const struct iovec *vec, apr_size_t nvec, apr_size_t *nbytes)
apr_status_t	apr_file_putc (char ch, apr_file_t *thefile)
apr_status_t	apr_file_getc (char *ch, apr_file_t *thefile)
apr_status_t	apr_file_ungetc (char ch, apr_file_t *thefile)
apr_status_t	apr_file_gets (char *str, int len, apr_file_t *thefile)
apr_status_t	apr_file_puts (const char *str, apr_file_t *thefile)
apr_status_t	apr_file_flush (apr_file_t *thefile)
apr_status_t	apr_file_sync (apr_file_t *thefile)
apr_status_t	apr_file_datasync (apr_file_t *thefile)
apr_status_t	apr_file_dup (apr_file_t **new_file, apr_file_t *old_file, apr_pool_t *p)
apr_status_t	apr_file_dup2 (apr_file_t *new_file, apr_file_t *old_file, apr_pool_t *p)
apr_status_t	apr_file_setaside (apr_file_t **new_file, apr_file_t *old_file, apr_pool_t *p)
apr_status_t	apr_file_buffer_set (apr_file_t *thefile, char *buffer, apr_size_t bufsize)
apr_size_t	apr_file_buffer_size_get (apr_file_t *thefile)
apr_status_t	apr_file_seek (apr_file_t *thefile, apr_seek_where_t where, apr_off_t *offset)
apr_status_t	apr_file_pipe_create (apr_file_t **in, apr_file_t **out, apr_pool_t *pool)
apr_status_t	apr_file_pipe_create_ex (apr_file_t **in, apr_file_t **out, apr_int32_t blocking, apr_pool_t *pool)
apr_status_t	apr_file_namedpipe_create (const char *filename, apr_fileperms_t perm, apr_pool_t *pool)
apr_status_t	apr_file_pipe_timeout_get (apr_file_t *thepipe, apr_interval_time_t *timeout)
apr_status_t	apr_file_pipe_timeout_set (apr_file_t *thepipe, apr_interval_time_t timeout)
apr_status_t	apr_file_lock (apr_file_t *thefile, int type)
apr_status_t	apr_file_unlock (apr_file_t *thefile)
apr_status_t	apr_file_name_get (const char **new_path, apr_file_t *thefile)
apr_status_t	apr_file_data_get (void **data, const char *key, apr_file_t *file)
apr_status_t	apr_file_data_set (apr_file_t *file, void *data, const char *key, apr_status_t(*cleanup)(void *))
int	apr_file_printf (apr_file_t *fptr, const char *format,...)
apr_status_t	apr_file_perms_set (const char *fname, apr_fileperms_t perms)
apr_status_t	apr_file_attrs_set (const char *fname, apr_fileattrs_t attributes, apr_fileattrs_t attr_mask, apr_pool_t *pool)
apr_status_t	apr_file_mtime_set (const char *fname, apr_time_t mtime, apr_pool_t *pool)
apr_status_t	apr_dir_make (const char *path, apr_fileperms_t perm, apr_pool_t *pool)
apr_status_t	apr_dir_make_recursive (const char *path, apr_fileperms_t perm, apr_pool_t *pool)
apr_status_t	apr_dir_remove (const char *path, apr_pool_t *pool)
apr_status_t	apr_file_info_get (apr_finfo_t *finfo, apr_int32_t wanted, apr_file_t *thefile)
apr_status_t	apr_file_trunc (apr_file_t *fp, apr_off_t offset)
apr_int32_t	apr_file_flags_get (apr_file_t *f)
apr_pool_t *	apr_file_pool_get (const apr_file_t *thefile)
apr_status_t	apr_file_inherit_set (apr_file_t *thefile)
apr_status_t	apr_file_inherit_unset (apr_file_t *thefile)
apr_status_t	apr_file_mktemp (apr_file_t **fp, char *templ, apr_int32_t flags, apr_pool_t *p)
apr_status_t	apr_temp_dir_get (const char **temp_dir, apr_pool_t *p)

---

Typedef Documentation

typedef struct apr_file_t apr_file_t

Structure for referencing files.

typedef apr_uint32_t apr_fileattrs_t

File attributes

typedef int apr_seek_where_t

Type to pass as whence argument to apr_file_seek.

---

Function Documentation

apr_status_t apr_dir_make	(	const char *	path,
		apr_fileperms_t	perm,
		apr_pool_t *	pool
	)

Create a new directory on the file system.

Parameters:

path	the path for the directory to be created. (use / on all systems)
perm	Permissions for the new directory.
pool	the pool to use.

apr_status_t apr_dir_make_recursive	(	const char *	path,
		apr_fileperms_t	perm,
		apr_pool_t *	pool
	)

Creates a new directory on the file system, but behaves like 'mkdir -p'. Creates intermediate directories as required. No error will be reported if PATH already exists.

Parameters:

path	the path for the directory to be created. (use / on all systems)
perm	Permissions for the new directory.
pool	the pool to use.

apr_status_t apr_dir_remove	(	const char *	path,
		apr_pool_t *	pool
	)

Remove directory from the file system.

Parameters:

path	the path for the directory to be removed. (use / on all systems)
pool	the pool to use.

Remarks:

Removing a directory which is in-use (e.g., the current working directory, or during apr_dir_read, or with an open file) is not portable.

apr_status_t apr_file_append	(	const char *	from_path,
		const char *	to_path,
		apr_fileperms_t	perms,
		apr_pool_t *	pool
	)

Append the specified file to another file.

Parameters:

from_path	The full path to the source file (use / on all systems)
to_path	The full path to the destination file (use / on all systems)
perms	Access permissions for the destination file if it is created. In place of the usual or'd combination of file permissions, the value APR_FILE_SOURCE_PERMS may be given, in which case the source file's permissions are copied.
pool	The pool to use.

Remarks:

The new file does not need to exist, it will be created if required.

apr_status_t apr_file_attrs_set	(	const char *	fname,
		apr_fileattrs_t	attributes,
		apr_fileattrs_t	attr_mask,
		apr_pool_t *	pool
	)

Set attributes of the specified file.

Parameters:

fname	The full path to the file (using / on all systems)
attributes	Or'd combination of APR_FILE_ATTR_READONLY - make the file readonly APR_FILE_ATTR_EXECUTABLE - make the file executable APR_FILE_ATTR_HIDDEN - make the file hidden
attr_mask	Mask of valid bits in attributes.
pool	the pool to use.

Remarks:

This function should be used in preference to explicit manipulation of the file permissions, because the operations to provide these attributes are platform specific and may involve more than simply setting permission bits.

Warning:

Platforms which do not implement this feature will return APR_ENOTIMPL.

apr_status_t apr_file_buffer_set	(	apr_file_t *	thefile,
		char *	buffer,
		apr_size_t	bufsize
	)

Give the specified apr file handle a new buffer

Parameters:

thefile	The file handle that is to be modified
buffer	The buffer
bufsize	The size of the buffer

Remarks:

It is possible to add a buffer to previously unbuffered file handles, the APR_BUFFERED flag will be added to the file handle's flags. Likewise, with buffer=NULL and bufsize=0 arguments it is possible to make a previously buffered file handle unbuffered.

apr_size_t apr_file_buffer_size_get

(

apr_file_t *

thefile

)

Get the size of any buffer for the specified apr file handle

Parameters:

thefile

The file handle

apr_status_t apr_file_close

(

apr_file_t *

file

)

Close the specified file.

Parameters:

file	The file descriptor to close.

apr_status_t apr_file_copy	(	const char *	from_path,
		const char *	to_path,
		apr_fileperms_t	perms,
		apr_pool_t *	pool
	)

Copy the specified file to another file.

Parameters:

from_path	The full path to the original file (using / on all systems)
to_path	The full path to the new file (using / on all systems)
perms	Access permissions for the new file if it is created. In place of the usual or'd combination of file permissions, the value APR_FILE_SOURCE_PERMS may be given, in which case the source file's permissions are copied.
pool	The pool to use.

Remarks:

The new file does not need to exist, it will be created if required.

Warning:

If the new file already exists, its contents will be overwritten.

apr_status_t apr_file_data_get	(	void **	data,
		const char *	key,
		apr_file_t *	file
	)

Return the data associated with the current file.

Parameters:

data	The user data associated with the file.
key	The key to use for retrieving data associated with this file.
file	The currently open file.

apr_status_t apr_file_data_set	(	apr_file_t *	file,
		void *	data,
		const char *	key,
		apr_status_t(*)(void *)	cleanup
	)

Set the data associated with the current file.

Parameters:

file	The currently open file.
data	The user data to associate with the file.
key	The key to use for associating data with the file.
cleanup	The cleanup routine to use when the file is destroyed.

apr_status_t apr_file_datasync

(

apr_file_t *

thefile

)

Transfer all file modified data to disk.

Parameters:

thefile

The file descriptor to sync

apr_status_t apr_file_dup	(	apr_file_t **	new_file,
		apr_file_t *	old_file,
		apr_pool_t *	p
	)

Duplicate the specified file descriptor.

Parameters:

new_file	The structure to duplicate into.
old_file	The file to duplicate.
p	The pool to use for the new file.

Remarks:

*new_file must point to a valid apr_file_t, or point to NULL.

apr_status_t apr_file_dup2	(	apr_file_t *	new_file,
		apr_file_t *	old_file,
		apr_pool_t *	p
	)

Duplicate the specified file descriptor and close the original

Parameters:

new_file	The old file that is to be closed and reused
old_file	The file to duplicate
p	The pool to use for the new file

Remarks:

new_file MUST point at a valid apr_file_t. It cannot be NULL.

apr_status_t apr_file_eof

(

apr_file_t *

fptr

)

Are we at the end of the file

Parameters:

fptr	The apr file we are testing.

Remarks:

Returns APR_EOF if we are at the end of file, APR_SUCCESS otherwise.

apr_int32_t apr_file_flags_get

(

apr_file_t *

f

)

Retrieve the flags that were passed into apr_file_open() when the file was opened.

Returns:

apr_int32_t the flags

apr_status_t apr_file_flush

(

apr_file_t *

thefile

)

Flush the file's buffer.

Parameters:

thefile

The file descriptor to flush

apr_status_t apr_file_getc	(	char *	ch,
		apr_file_t *	thefile
	)

Read a character from the specified file.

Parameters:

ch	The character to read into
thefile	The file descriptor to read from

apr_status_t apr_file_gets	(	char *	str,
		int	len,
		apr_file_t *	thefile
	)

Read a line from the specified file

Parameters:

str	The buffer to store the string in.
len	The length of the string
thefile	The file descriptor to read from

Remarks:

The buffer will be NUL-terminated if any characters are stored. The newline at the end of the line will not be stripped.

apr_status_t apr_file_info_get	(	apr_finfo_t *	finfo,
		apr_int32_t	wanted,
		apr_file_t *	thefile
	)

get the specified file's stats.

Parameters:

finfo	Where to store the information about the file.
wanted	The desired apr_finfo_t fields, as a bit flag of APR_FINFO_ values
thefile	The file to get information about.

apr_status_t apr_file_inherit_set

(

apr_file_t *

thefile

)

Set a file to be inherited by child processes.

apr_status_t apr_file_inherit_unset

(

apr_file_t *

thefile

)

Unset a file from being inherited by child processes.

apr_status_t apr_file_link	(	const char *	from_path,
		const char *	to_path
	)

Create a hard link to the specified file.

Parameters:

from_path	The full path to the original file (using / on all systems)
to_path	The full path to the new file (using / on all systems)

Remarks:

Both files must reside on the same device.

apr_status_t apr_file_lock	(	apr_file_t *	thefile,
		int	type
	)

file (un)locking functions. Establish a lock on the specified, open file. The lock may be advisory or mandatory, at the discretion of the platform. The lock applies to the file as a whole, rather than a specific range. Locks are established on a per-thread/process basis; a second lock by the same thread will not block.

Parameters:

thefile	The file to lock.
type	The type of lock to establish on the file.

apr_status_t apr_file_mktemp	(	apr_file_t **	fp,
		char *	templ,
		apr_int32_t	flags,
		apr_pool_t *	p
	)

Open a temporary file

Parameters:

fp	The apr file to use as a temporary file.
templ	The template to use when creating a temp file.
flags	The flags to open the file with. If this is zero, the file is opened with APR_CREATE | APR_READ | APR_WRITE | APR_EXCL | APR_DELONCLOSE
p	The pool to allocate the file out of.

Remarks:

This function generates a unique temporary file name from template. The last six characters of template must be XXXXXX and these are replaced with a string that makes the filename unique. Since it will be modified, template must not be a string constant, but should be declared as a character array.

apr_status_t apr_file_mtime_set	(	const char *	fname,
		apr_time_t	mtime,
		apr_pool_t *	pool
	)

Set the mtime of the specified file.

Parameters:

fname	The full path to the file (using / on all systems)
mtime	The mtime to apply to the file.
pool	The pool to use.

Warning:

Platforms which do not implement this feature will return APR_ENOTIMPL.

apr_status_t apr_file_name_get	(	const char **	new_path,
		apr_file_t *	thefile
	)

accessor and general file_io functions. return the file name of the current file.

Parameters:

new_path	The path of the file.
thefile	The currently open file.

apr_status_t apr_file_namedpipe_create	(	const char *	filename,
		apr_fileperms_t	perm,
		apr_pool_t *	pool
	)

Create a named pipe.

Parameters:

filename	The filename of the named pipe
perm	The permissions for the newly created pipe.
pool	The pool to operate on.

apr_status_t apr_file_open	(	apr_file_t **	newf,
		const char *	fname,
		apr_int32_t	flag,
		apr_fileperms_t	perm,
		apr_pool_t *	pool
	)

Open the specified file.

Parameters:

newf	The opened file descriptor.
fname	The full path to the file (using / on all systems)
flag	Or'ed value of: APR_READ open for reading APR_WRITE open for writing APR_CREATE create the file if not there APR_APPEND file ptr is set to end prior to all writes APR_TRUNCATE set length to zero if file exists APR_BINARY not a text file (This flag is ignored on UNIX because it has no meaning) APR_BUFFERED buffer the data. Default is non-buffered APR_EXCL return error if APR_CREATE and file exists APR_DELONCLOSE delete the file after closing. APR_XTHREAD Platform dependent tag to open the file for use across multiple threads APR_SHARELOCK Platform dependent support for higher level locked read/write access to support writes across process/machines APR_FILE_NOCLEANUP Do not register a cleanup with the pool passed in on the pool argument (see below). The apr_os_file_t handle in apr_file_t will not be closed when the pool is destroyed. APR_SENDFILE_ENABLED Open with appropriate platform semantics for sendfile operations. Advisory only, apr_socket_sendfile does not check this flag.
perm	Access permissions for file.
pool	The pool to use.

Remarks:

If perm is APR_OS_DEFAULT and the file is being created, appropriate default permissions will be used.

By default, the returned file descriptor will not be inherited by child processes created by apr_proc_create(). This can be changed using apr_file_inherit_set().

apr_status_t apr_file_open_flags_stderr	(	apr_file_t **	thefile,
		apr_int32_t	flags,
		apr_pool_t *	pool
	)

open standard error as an apr file pointer, with flags.

Parameters:

thefile	The apr file to use as stderr.
flags	The flags to open the file with. Only the APR_EXCL, APR_BUFFERED, APR_XTHREAD, APR_SHARELOCK, APR_SENDFILE_ENABLED and APR_LARGEFILE flags should be used. The APR_WRITE flag will be set unconditionally.
pool	The pool to allocate the file out of.

Remarks:

See remarks for apr_file_open_stderr.

apr_status_t apr_file_open_flags_stdin	(	apr_file_t **	thefile,
		apr_int32_t	flags,
		apr_pool_t *	pool
	)

open standard input as an apr file pointer, with flags.

Parameters:

thefile	The apr file to use as stdin.
flags	The flags to open the file with. Only the APR_EXCL, APR_BUFFERED, APR_XTHREAD, APR_SHARELOCK, APR_SENDFILE_ENABLED and APR_LARGEFILE flags should be used. The APR_READ flag will be set unconditionally.
pool	The pool to allocate the file out of.

Remarks:

See remarks for apr_file_open_stderr.

apr_status_t apr_file_open_flags_stdout	(	apr_file_t **	thefile,
		apr_int32_t	flags,
		apr_pool_t *	pool
	)

open standard output as an apr file pointer, with flags.

Parameters:

thefile	The apr file to use as stdout.
flags	The flags to open the file with. Only the APR_EXCL, APR_BUFFERED, APR_XTHREAD, APR_SHARELOCK, APR_SENDFILE_ENABLED and APR_LARGEFILE flags should be used. The APR_WRITE flag will be set unconditionally.
pool	The pool to allocate the file out of.

Remarks:

See remarks for apr_file_open_stderr.

apr_status_t apr_file_open_stderr	(	apr_file_t **	thefile,
		apr_pool_t *	pool
	)

Open standard error as an apr file pointer.

Parameters:

thefile	The apr file to use as stderr.
pool	The pool to allocate the file out of.

Remarks:

The only reason that the apr_file_open_std* functions exist is that you may not always have a stderr/out/in on Windows. This is generally a problem with newer versions of Windows and services.

The other problem is that the C library functions generally work differently on Windows and Unix. So, by using apr_file_open_std* functions, you can get a handle to an APR struct that works with the APR functions which are supposed to work identically on all platforms.

apr_status_t apr_file_open_stdin	(	apr_file_t **	thefile,
		apr_pool_t *	pool
	)

open standard input as an apr file pointer.

Parameters:

thefile	The apr file to use as stdin.
pool	The pool to allocate the file out of.

Remarks:

See remarks for apr_file_open_stderr.

apr_status_t apr_file_open_stdout	(	apr_file_t **	thefile,
		apr_pool_t *	pool
	)

open standard output as an apr file pointer.

Parameters:

thefile	The apr file to use as stdout.
pool	The pool to allocate the file out of.

Remarks:

See remarks for apr_file_open_stderr.

apr_status_t apr_file_perms_set	(	const char *	fname,
		apr_fileperms_t	perms
	)

set the specified file's permission bits.

Parameters:

fname	The file (name) to apply the permissions to.
perms	The permission bits to apply to the file.

Warning:

Some platforms may not be able to apply all of the available permission bits; APR_INCOMPLETE will be returned if some permissions are specified which could not be set.

Platforms which do not implement this feature will return APR_ENOTIMPL.

apr_status_t apr_file_pipe_create	(	apr_file_t **	in,
		apr_file_t **	out,
		apr_pool_t *	pool
	)

Create an anonymous pipe.

Parameters:

in	The newly created pipe's file for reading.
out	The newly created pipe's file for writing.
pool	The pool to operate on.

Remarks:

By default, the returned file descriptors will be inherited by child processes created using apr_proc_create(). This can be changed using apr_file_inherit_unset().

Bug:

Some platforms cannot toggle between blocking and nonblocking, and when passing a pipe as a standard handle to an application which does not expect it, a non-blocking stream will fluxor the client app.

Deprecated:

See also:

apr_file_pipe_create_ex

apr_status_t apr_file_pipe_create_ex	(	apr_file_t **	in,
		apr_file_t **	out,
		apr_int32_t	blocking,
		apr_pool_t *	pool
	)

Create an anonymous pipe which portably supports async timeout options.

Parameters:

in	The newly created pipe's file for reading.
out	The newly created pipe's file for writing.
blocking	one of these values defined in apr_thread_proc.h;
pool	The pool to operate on. APR_FULL_BLOCK APR_READ_BLOCK APR_WRITE_BLOCK APR_FULL_NONBLOCK

Remarks:

By default, the returned file descriptors will be inherited by child processes created using apr_proc_create(). This can be changed using apr_file_inherit_unset().

Some platforms cannot toggle between blocking and nonblocking, and when passing a pipe as a standard handle to an application which does not expect it, a non-blocking stream will fluxor the client app. Use this function rather than apr_file_pipe_create to create pipes where one or both ends require non-blocking semantics.

apr_status_t apr_file_pipe_timeout_get	(	apr_file_t *	thepipe,
		apr_interval_time_t *	timeout
	)

Get the timeout value for a pipe or manipulate the blocking state.

Parameters:

thepipe	The pipe we are getting a timeout for.
timeout	The current timeout value in microseconds.

apr_status_t apr_file_pipe_timeout_set	(	apr_file_t *	thepipe,
		apr_interval_time_t	timeout
	)

Set the timeout value for a pipe or manipulate the blocking state.

Parameters:

thepipe	The pipe we are setting a timeout on.
timeout	The timeout value in microseconds. Values < 0 mean wait forever, 0 means do not wait at all.

apr_pool_t* apr_file_pool_get

(

const apr_file_t *

thefile

)

Get the pool used by the file.

int apr_file_printf	(	apr_file_t *	fptr,
		const char *	format,
			...
	)

Write a string to a file using a printf format.

Parameters:

fptr	The file to write to.
format	The format string
...	The values to substitute in the format string

Returns:

The number of bytes written

apr_status_t apr_file_putc	(	char	ch,
		apr_file_t *	thefile
	)

Write a character into the specified file.

Parameters:

ch	The character to write.
thefile	The file descriptor to write to

apr_status_t apr_file_puts	(	const char *	str,
		apr_file_t *	thefile
	)

Write the string into the specified file.

Parameters:

str	The string to write.
thefile	The file descriptor to write to

apr_status_t apr_file_read	(	apr_file_t *	thefile,
		void *	buf,
		apr_size_t *	nbytes
	)

Read data from the specified file.

Parameters:

thefile	The file descriptor to read from.
buf	The buffer to store the data to.
nbytes	On entry, the number of bytes to read; on exit, the number of bytes read.

Remarks:

apr_file_read will read up to the specified number of bytes, but never more. If there isn't enough data to fill that number of bytes, all of the available data is read. The third argument is modified to reflect the number of bytes read. If a char was put back into the stream via ungetc, it will be the first character returned.

It is not possible for both bytes to be read and an APR_EOF or other error to be returned. APR_EINTR is never returned.

apr_status_t apr_file_read_full	(	apr_file_t *	thefile,
		void *	buf,
		apr_size_t	nbytes,
		apr_size_t *	bytes_read
	)

Read data from the specified file, ensuring that the buffer is filled before returning.

Parameters:

thefile	The file descriptor to read from.
buf	The buffer to store the data to.
nbytes	The number of bytes to read.
bytes_read	If non-NULL, this will contain the number of bytes read.

Remarks:

apr_file_read will read up to the specified number of bytes, but never more. If there isn't enough data to fill that number of bytes, then the process/thread will block until it is available or EOF is reached. If a char was put back into the stream via ungetc, it will be the first character returned.

It is possible for both bytes to be read and an error to be returned. And if *bytes_read is less than nbytes, an accompanying error is _always_ returned.

APR_EINTR is never returned.

apr_status_t apr_file_remove	(	const char *	path,
		apr_pool_t *	pool
	)

Delete the specified file.

Parameters:

path	The full path to the file (using / on all systems)
pool	The pool to use.

Remarks:

If the file is open, it won't be removed until all instances are closed.

apr_status_t apr_file_rename	(	const char *	from_path,
		const char *	to_path,
		apr_pool_t *	pool
	)

Rename the specified file.

Parameters:

from_path	The full path to the original file (using / on all systems)
to_path	The full path to the new file (using / on all systems)
pool	The pool to use.

Warning:

If a file exists at the new location, then it will be overwritten. Moving files or directories across devices may not be possible.

apr_status_t apr_file_seek	(	apr_file_t *	thefile,
		apr_seek_where_t	where,
		apr_off_t *	offset
	)

Move the read/write file offset to a specified byte within a file.

Parameters:

thefile	The file descriptor
where	How to move the pointer, one of: APR_SET -- set the offset to offset APR_CUR -- add the offset to the current position APR_END -- add the offset to the current file size
offset	The offset to move the pointer to.

Remarks:

The third argument is modified to be the offset the pointer was actually moved to.

apr_status_t apr_file_setaside	(	apr_file_t **	new_file,
		apr_file_t *	old_file,
		apr_pool_t *	p
	)

Move the specified file descriptor to a new pool

Parameters:

new_file	Pointer in which to return the new apr_file_t
old_file	The file to move
p	The pool to which the descriptor is to be moved

Remarks:

Unlike apr_file_dup2(), this function doesn't do an OS dup() operation on the underlying descriptor; it just moves the descriptor's apr_file_t wrapper to a new pool.

The new pool need not be an ancestor of old_file's pool.

After calling this function, old_file may not be used

apr_status_t apr_file_sync

(

apr_file_t *

thefile

)

Transfer all file modified data and metadata to disk.

Parameters:

thefile

The file descriptor to sync

apr_status_t apr_file_trunc	(	apr_file_t *	fp,
		apr_off_t	offset
	)

Truncate the file's length to the specified offset

Parameters:

fp	The file to truncate
offset	The offset to truncate to.

Remarks:

The read/write file offset is repositioned to offset.

apr_status_t apr_file_ungetc	(	char	ch,
		apr_file_t *	thefile
	)

Put a character back onto a specified stream.

Parameters:

ch	The character to write.
thefile	The file descriptor to write to

apr_status_t apr_file_unlock

(

apr_file_t *

thefile

)

Remove any outstanding locks on the file.

Parameters:

thefile

The file to unlock.

apr_status_t apr_file_write	(	apr_file_t *	thefile,
		const void *	buf,
		apr_size_t *	nbytes
	)

Write data to the specified file.

Parameters:

thefile	The file descriptor to write to.
buf	The buffer which contains the data.
nbytes	On entry, the number of bytes to write; on exit, the number of bytes written.

Remarks:

apr_file_write will write up to the specified number of bytes, but never more. If the OS cannot write that many bytes, it will write as many as it can. The third argument is modified to reflect the * number of bytes written.

It is possible for both bytes to be written and an error to be returned. APR_EINTR is never returned.

apr_status_t apr_file_write_full	(	apr_file_t *	thefile,
		const void *	buf,
		apr_size_t	nbytes,
		apr_size_t *	bytes_written
	)

Write data to the specified file, ensuring that all of the data is written before returning.

Parameters:

thefile	The file descriptor to write to.
buf	The buffer which contains the data.
nbytes	The number of bytes to write.
bytes_written	If non-NULL, set to the number of bytes written.

Remarks:

apr_file_write will write up to the specified number of bytes, but never more. If the OS cannot write that many bytes, the process/thread will block until they can be written. Exceptional error such as "out of space" or "pipe closed" will terminate with an error.

It is possible for both bytes to be written and an error to be returned. And if *bytes_written is less than nbytes, an accompanying error is _always_ returned.

APR_EINTR is never returned.

apr_status_t apr_file_writev	(	apr_file_t *	thefile,
		const struct iovec *	vec,
		apr_size_t	nvec,
		apr_size_t *	nbytes
	)

Write data from iovec array to the specified file.

Parameters:

thefile	The file descriptor to write to.
vec	The array from which to get the data to write to the file.
nvec	The number of elements in the struct iovec array. This must be smaller than APR_MAX_IOVEC_SIZE. If it isn't, the function will fail with APR_EINVAL.
nbytes	The number of bytes written.

Remarks:

It is possible for both bytes to be written and an error to be returned. APR_EINTR is never returned.

apr_file_writev is available even if the underlying operating system doesn't provide writev().

apr_status_t apr_file_writev_full	(	apr_file_t *	thefile,
		const struct iovec *	vec,
		apr_size_t	nvec,
		apr_size_t *	nbytes
	)

Write data from iovec array to the specified file, ensuring that all of the data is written before returning.

Parameters:

thefile	The file descriptor to write to.
vec	The array from which to get the data to write to the file.
nvec	The number of elements in the struct iovec array. This must be smaller than APR_MAX_IOVEC_SIZE. If it isn't, the function will fail with APR_EINVAL.
nbytes	The number of bytes written.

Remarks:

apr_file_writev_full is available even if the underlying operating system doesn't provide writev().

apr_status_t apr_temp_dir_get	(	const char **	temp_dir,
		apr_pool_t *	p
	)

Find an existing directory suitable as a temporary storage location.

Parameters:

temp_dir	The temp directory.
p	The pool to use for any necessary allocations.

Remarks:

This function uses an algorithm to search for a directory that an an application can use for temporary storage.