libqcow(3) Library Functions Manual libqcow(3)

# [NAME](#NAME)

`libqcow.h` — Library to access the QEMU Copy-On-Write (QCOW) image format

# [LIBRARY](#LIBRARY)

library “libqcow”

# [SYNOPSIS](#SYNOPSIS)

`#include <libqcow.h>`

Support functions  
`const char *`  
`libqcow_get_version`(`void`);

`int`  
`libqcow_get_access_flags_read`(`void`);

`int`  
`libqcow_get_access_flags_read_write`(`void`);

`int`  
`libqcow_get_access_flags_write`(`void`);

`int`  
`libqcow_get_codepage`(`int *codepage, libqcow_error_t **error`);

`int`  
`libqcow_set_codepage`(`int codepage, libqcow_error_t **error`);

`int`  
`libqcow_check_file_signature`(`const char *filename, libqcow_error_t **error`);

Available when compiled with wide character string support:  
`int`  
`libqcow_check_file_signature_wide`(`const wchar_t *filename, libqcow_error_t **error`);

Available when compiled with libbfio support:  
`int`  
`libqcow_check_file_signature_file_io_handle`(`libbfio_handle_t *bfio_handle, libqcow_error_t **error`);

Notify functions  
`void`  
`libqcow_notify_set_verbose`(`int verbose`);

`int`  
`libqcow_notify_set_stream`(`FILE *stream, libqcow_error_t **error`);

`int`  
`libqcow_notify_stream_open`(`const char *filename, libqcow_error_t **error`);

`int`  
`libqcow_notify_stream_close`(`libqcow_error_t **error`);

Error functions  
`void`  
`libqcow_error_free`(`libqcow_error_t **error`);

`int`  
`libqcow_error_fprint`(`libqcow_error_t *error, FILE *stream`);

`int`  
`libqcow_error_sprint`(`libqcow_error_t *error, char *string, size_t size`);

`int`  
`libqcow_error_backtrace_fprint`(`libqcow_error_t *error, FILE *stream`);

`int`  
`libqcow_error_backtrace_sprint`(`libqcow_error_t *error, char *string, size_t size`);

File functions  
`int`  
`libqcow_file_initialize`(`libqcow_file_t **file, libqcow_error_t **error`);

`int`  
`libqcow_file_free`(`libqcow_file_t **file, libqcow_error_t **error`);

`int`  
`libqcow_file_signal_abort`(`libqcow_file_t *file, libqcow_error_t **error`);

`int`  
`libqcow_file_open`(`libqcow_file_t *file, const char *filename, int access_flags, libqcow_error_t **error`);

`int`  
`libqcow_file_close`(`libqcow_file_t *file, libqcow_error_t **error`);

`ssize_t`  
`libqcow_file_read_buffer`(`libqcow_file_t *file, void *buffer, size_t buffer_size, libqcow_error_t **error`);

`ssize_t`  
`libqcow_file_read_buffer_at_offset`(`libqcow_file_t *file, void *buffer, size_t buffer_size, off64_t offset, libqcow_error_t **error`);

`ssize_t`  
`libqcow_file_write_buffer`(`libqcow_file_t *file, const void *buffer, size_t buffer_size, libqcow_error_t **error`);

`ssize_t`  
`libqcow_file_write_buffer_at_offset`(`libqcow_file_t *file, const void *buffer, size_t buffer_size, off64_t offset, libqcow_error_t **error`);

`off64_t`  
`libqcow_file_seek_offset`(`libqcow_file_t *file, off64_t offset, int whence, libqcow_error_t **error`);

`int`  
`libqcow_file_get_offset`(`libqcow_file_t *file, off64_t *offset, libqcow_error_t **error`);

`int`  
`libqcow_file_get_format_version`(`libqcow_file_t *file, uint32_t *format_version, libqcow_error_t **error`);

`int`  
`libqcow_file_get_encryption_method`(`libqcow_file_t *file, uint32_t *encryption_method, libqcow_error_t **error`);

`int`  
`libqcow_file_set_keys`(`libqcow_file_t *file, const uint8_t *key, size_t key_size, libqcow_error_t **error`);

`int`  
`libqcow_file_set_utf8_password`(`libqcow_file_t *file, const uint8_t *utf8_string, size_t utf8_string_length, libqcow_error_t **error`);

`int`  
`libqcow_file_set_utf16_password`(`libqcow_file_t *file, const uint16_t *utf16_string, size_t utf16_string_length, libqcow_error_t **error`);

Available when compiled with wide character string support:  
`int`  
`libqcow_file_open_wide`(`libqcow_file_t *file, const wchar_t *filename, int access_flags, libqcow_error_t **error`);

Available when compiled with libbfio support:  
`int`  
`libqcow_file_open_file_io_handle`(`libqcow_file_t *file, libbfio_handle_t *file_io_handle, int access_flags, libqcow_error_t **error`);

Meta data functions  
`int`  
`libqcow_file_get_media_size`(`libqcow_file_t *file, size64_t *media_size, libqcow_error_t **error`);

# [DESCRIPTION](#DESCRIPTION)

The [`libqcow_get_version`](#libqcow_get_version)() function is used to retrieve the library version.

# [RETURN VALUES](#RETURN_VALUES)

Most of the functions return NULL or -1 on error, dependent on the return type. For the actual return values see "libqcow.h".

# [ENVIRONMENT](#ENVIRONMENT)

None

# [FILES](#FILES)

None

# [NOTES](#NOTES)

libqcow allows to be compiled with wide character support (wchar\_t).

To compile libqcow with wide character support use: `./configure --enable-wide-character-type=yes`  
or define: `_UNICODE`  
or `UNICODE`  
during compilation.

`LIBQCOW_WIDE_CHARACTER_TYPE`  
in libqcow/features.h can be used to determine if libqcow was compiled with wide character support.

# [BUGS](#BUGS)

Please report bugs of any kind on the project issue tracker: https://github.com/libyal/libqcow/issues

# [AUTHOR](#AUTHOR)

These man pages are generated from "libqcow.h".

# [COPYRIGHT](#COPYRIGHT)

Copyright (C) 2010-2018, Joachim Metz &lt;joachim.metz@gmail.com&gt;.

This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

# [SEE ALSO](#SEE_ALSO)

the libqcow.h include file

October 22, 2016 libqcow

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Document: libqcow(3) from longhorn-libqcow 1.0.0-r3 (Chainguard OS)
Source: https://github.com/longhorn/libqcow