[platform/upstream/glib2.0.git] / docs / reference / glib / tmpl / fileutils.sgml

<!-- ##### SECTION Title ##### -->
File Utilities

<!-- ##### SECTION Short_Description ##### -->
various file-related functions

<!-- ##### SECTION Long_Description ##### -->
<para>
There is a group of functions which wrap the common POSIX functions 
dealing with filenames (g_open(), g_rename(), g_mkdir(), g_stat(), 
g_unlink(), g_remove(), g_fopen(), g_freopen()). The point of these 
wrappers is to make it possible to handle file names with any Unicode 
characters in them on Windows without having to use ifdefs and the 
wide character API in the application code.
</para>
<para>
The pathname argument should be in the GLib file name encoding. On
POSIX this is the actual on-disk encoding which might correspond to
the locale settings of the process (or the 
<envar>G_FILENAME_ENCODING</envar> environment variable), or not.
</para>
<para>
On Windows the GLib file name encoding is UTF-8. Note that the
Microsoft C library does not use UTF-8, but has separate APIs for
current system code page and wide characters (UTF-16). The GLib
wrappers call the wide character API if present (on modern Windows
systems), otherwise convert to/from the system code page.
</para>

<para>
Another group of functions allows to open and read directories
in the GLib file name encoding. These are g_dir_open(), 
g_dir_read_name(), g_dir_rewind(), g_dir_close().
</para>

<!-- ##### SECTION See_Also ##### -->
<para>

</para>

<!-- ##### SECTION Stability_Level ##### -->


<!-- ##### ENUM GFileError ##### -->
<para>
Values corresponding to <literal>errno</literal> codes returned from file operations
on UNIX. Unlike <literal>errno</literal> codes, #GFileError values are available on 
all systems, even Windows. The exact meaning of each code depends on what
sort of file operation you were performing; the UNIX documentation
gives more details. The following error code descriptions come 
from the GNU C Library manual, and are under the copyright
of that manual.
</para>

<para>
It's not very portable to make detailed assumptions about exactly
which errors will be returned from a given operation. Some errors
don't occur on some systems, etc., sometimes there are subtle
differences in when a system will report a given error, etc.
</para>

@G_FILE_ERROR_EXIST: Operation not permitted; only the owner of the
     file (or other resource) or processes with special privileges can
     perform the operation.
@G_FILE_ERROR_ISDIR: File is a directory; you cannot open a directory
     for writing, or create or remove hard links to it.
@G_FILE_ERROR_ACCES: Permission denied; the file permissions do not
     allow the attempted operation.
@G_FILE_ERROR_NAMETOOLONG: Filename too long.
@G_FILE_ERROR_NOENT: No such file or directory.  This is a "file
     doesn't exist" error for ordinary files that are referenced in
     contexts where they are expected to already exist.
@G_FILE_ERROR_NOTDIR: A file that isn't a directory was specified when
     a directory is required.
@G_FILE_ERROR_NXIO: No such device or address.  The system tried to
     use the device represented by a file you specified, and it
     couldn't find the device.  This can mean that the device file was
     installed incorrectly, or that the physical device is missing or
     not correctly attached to the computer.
@G_FILE_ERROR_NODEV: This file is of a type that doesn't support
     mapping.
@G_FILE_ERROR_ROFS: The directory containing the new link can't be
          modified because it's on a read-only file system.
@G_FILE_ERROR_TXTBSY: Text file busy.
@G_FILE_ERROR_FAULT: You passed in a pointer to bad memory.
  (GLib won't reliably return this, don't pass in pointers to bad
  memory.)
@G_FILE_ERROR_LOOP: Too many levels of symbolic links were encountered
  in looking up a file name.  This often indicates a cycle of symbolic
  links.
@G_FILE_ERROR_NOSPC: No space left on device; write operation on a
  file failed because the disk is full.
@G_FILE_ERROR_NOMEM: No memory available.  The system cannot allocate
     more virtual memory because its capacity is full.
@G_FILE_ERROR_MFILE: The current process has too many files open and
     can't open any more.  Duplicate descriptors do count toward this
     limit.
@G_FILE_ERROR_NFILE: There are too many distinct file openings in the
     entire system.
@G_FILE_ERROR_BADF: Bad file descriptor; for example, I/O on a
     descriptor that has been closed or reading from a descriptor open
     only for writing (or vice versa).
@G_FILE_ERROR_INVAL: Invalid argument.  This is used to indicate
     various kinds of problems with passing the wrong argument to a
     library function.
@G_FILE_ERROR_PIPE: Broken pipe; there is no process reading from the
     other end of a pipe.  Every library function that returns this
     error code also generates a `SIGPIPE' signal; this signal
     terminates the program if not handled or blocked.  Thus, your
     program will never actually see this code unless it has handled or
     blocked `SIGPIPE'.
@G_FILE_ERROR_AGAIN: Resource temporarily unavailable; the call might
     work if you try again later.
@G_FILE_ERROR_INTR: Interrupted function call; an asynchronous signal
     occurred and prevented completion of the call.  When this
     happens, you should try the call again.
@G_FILE_ERROR_IO: Input/output error; usually used for physical read
    or write errors. i.e. the disk or other physical device hardware
    is returning errors.
@G_FILE_ERROR_PERM: Operation not permitted; only the owner of the
     file (or other resource) or processes with special privileges can
     perform the operation.
@G_FILE_ERROR_NOSYS: Function not implemented; this indicates that the
    system is missing some functionality.
@G_FILE_ERROR_FAILED: Does not correspond to a UNIX error code; this
  is the standard "failed for unspecified reason" error code present in 
  all #GError error code enumerations. Returned if no specific
  code applies.

<!-- ##### MACRO G_FILE_ERROR ##### -->
<para>
Error domain for file operations. Errors in this domain will
be from the #GFileError enumeration. See #GError for information on 
error domains.
</para>



<!-- ##### ENUM GFileTest ##### -->
<para>
A test to perform on a file using g_file_test().
</para>

@G_FILE_TEST_IS_REGULAR: %TRUE if the file is a regular file (not a directory).
    Note that this test will also return %TRUE if the tested file is a symlink
    to a regular file.
@G_FILE_TEST_IS_SYMLINK: %TRUE if the file is a symlink.
@G_FILE_TEST_IS_DIR: %TRUE if the file is a directory.
@G_FILE_TEST_IS_EXECUTABLE: %TRUE if the file is executable.
@G_FILE_TEST_EXISTS: %TRUE if the file exists. 
    It may or may not be a regular file.

<!-- ##### FUNCTION g_file_error_from_errno ##### -->
<para>

</para>

@err_no: 
@Returns: 


<!-- ##### FUNCTION g_file_get_contents ##### -->
<para>

</para>

@filename: 
@contents: 
@length: 
@error: 
@Returns: 


<!-- ##### FUNCTION g_file_set_contents ##### -->
<para>

</para>

@filename: 
@contents: 
@length: 
@error: 
@Returns: 


<!-- ##### FUNCTION g_file_test ##### -->
<para>

</para>

@filename: 
@test: 
@Returns: 


<!-- ##### FUNCTION g_mkstemp ##### -->
<para>

</para>

@tmpl: 
@Returns: 


<!-- ##### FUNCTION g_mkstemp_full ##### -->
<para>

</para>

@tmpl: 
@flags: 
@mode: 
@Returns: 


<!-- ##### FUNCTION g_file_open_tmp ##### -->
<para>

</para>

@tmpl: 
@name_used: 
@error: 
@Returns: 


<!-- ##### FUNCTION g_file_read_link ##### -->
<para>

</para>

@filename: 
@error: 
@Returns: 


<!-- ##### FUNCTION g_mkdir_with_parents ##### -->
<para>

</para>

@pathname: 
@mode: 
@Returns: 


<!-- ##### STRUCT GDir ##### -->
<para>
An opaque structure representing an opened directory.
</para>


<!-- ##### FUNCTION g_dir_open ##### -->
<para>

</para>

@path: 
@flags: 
@error: 
@Returns: 


<!-- ##### FUNCTION g_dir_read_name ##### -->
<para>

</para>

@dir: 
@Returns: 


<!-- ##### FUNCTION g_dir_rewind ##### -->
<para>

</para>

@dir: 


<!-- ##### FUNCTION g_dir_close ##### -->
<para>

</para>

@dir: 


<!-- ##### STRUCT GMappedFile ##### -->
<para>
The #GMappedFile represents a file mapping created with
g_mapped_file_new(). It has only private members and should
not be accessed directly.
</para>


<!-- ##### FUNCTION g_mapped_file_new ##### -->
<para>

</para>

@filename: 
@writable: 
@error: 
@Returns: 


<!-- ##### FUNCTION g_mapped_file_ref ##### -->
<para>

</para>

@file: 
@Returns: 


<!-- ##### FUNCTION g_mapped_file_unref ##### -->
<para>

</para>

@file: 


<!-- ##### FUNCTION g_mapped_file_free ##### -->
<para>

</para>

@file: 


<!-- ##### FUNCTION g_mapped_file_get_length ##### -->
<para>

</para>

@file: 
@Returns: 


<!-- ##### FUNCTION g_mapped_file_get_contents ##### -->
<para>

</para>

@file: 
@Returns: 


<!-- ##### FUNCTION g_open ##### -->
<para>

</para>

@filename: 
@flags: 
@mode: 
@Returns: 


<!-- ##### FUNCTION g_rename ##### -->
<para>

</para>

@oldfilename: 
@newfilename: 
@Returns: 


<!-- ##### FUNCTION g_mkdir ##### -->
<para>

</para>

@filename: 
@mode: 
@Returns: 


<!-- ##### FUNCTION g_stat ##### -->
<para>

</para>

@filename: 
@buf: 
@Returns: 


<!-- ##### FUNCTION g_lstat ##### -->
<para>

</para>

@filename: 
@buf: 
@Returns: 


<!-- ##### FUNCTION g_unlink ##### -->
<para>

</para>

@filename: 
@Returns: 


<!-- ##### FUNCTION g_remove ##### -->
<para>

</para>

@filename: 
@Returns: 


<!-- ##### FUNCTION g_rmdir ##### -->
<para>

</para>

@filename: 
@Returns: 


<!-- ##### FUNCTION g_fopen ##### -->
<para>

</para>

@filename: 
@mode: 
@Returns: 


<!-- ##### FUNCTION g_freopen ##### -->
<para>

</para>

@filename: 
@mode: 
@stream: 
@Returns: 


<!-- ##### FUNCTION g_chmod ##### -->
<para>

</para>

@filename: 
@mode: 
@Returns: 


<!-- ##### FUNCTION g_access ##### -->
<para>

</para>

@filename: 
@mode: 
@Returns: 


<!-- ##### FUNCTION g_creat ##### -->
<para>

</para>

@filename: 
@mode: 
@Returns: 


<!-- ##### FUNCTION g_chdir ##### -->
<para>

</para>

@path: 
@Returns: 


<!-- ##### FUNCTION g_utime ##### -->
<para>

</para>

@filename: 
@utb: 
@Returns: