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Diffstat (limited to 'src/lib/ffmpeg-2.7/avio.pas')
| -rw-r--r-- | src/lib/ffmpeg-2.7/avio.pas | 744 |
1 files changed, 744 insertions, 0 deletions
diff --git a/src/lib/ffmpeg-2.7/avio.pas b/src/lib/ffmpeg-2.7/avio.pas new file mode 100644 index 00000000..ae9dd5ef --- /dev/null +++ b/src/lib/ffmpeg-2.7/avio.pas @@ -0,0 +1,744 @@ +(* + * copyright (c) 2001 Fabrice Bellard + * + * This file is part of FFmpeg. + * + * FFmpeg is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * FFmpeg is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * You should have received a copy of the GNU Lesser General Public + * License along with FFmpeg; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA + * + * This is a part of Pascal porting of ffmpeg. + * - Originally by Victor Zinetz for Delphi and Free Pascal on Windows. + * - For Mac OS X, some modifications were made by The Creative CAT, denoted as CAT + * in the source codes. + * - Changes and updates by the UltraStar Deluxe Team + * + * Conversion of libavformat/avio.h + * unbuffered I/O operations + * @warning This file has to be considered an internal but installed + * header, so it should not be directly included in your projects. + * + * update to + * avformat version: 56.4.101 + *) + +unit avio; + +{$IFDEF FPC} + {$MODE DELPHI } + {$PACKENUM 4} (* use 4-byte enums *) + {$PACKRECORDS C} (* C/C++-compatible record packing *) +{$ELSE} + {$MINENUMSIZE 4} (* use 4-byte enums *) +{$ENDIF} + +{$I switches.inc} + +interface + +uses + ctypes, + {$IFDEF UNIX} + BaseUnix, // for SEEK_CUR + {$ENDIF} + avcodec, + avutil, + SysUtils, + UConfig; + +(** + * Those FF_API_* defines are not part of public API. + * They may change, break or disappear at any time. + *) +const + FF_API_URL_CLASS = (LIBAVFORMAT_VERSION_MAJOR >= 53); + +const + AVIO_SEEKABLE_NORMAL = 0001; (**< Seeking works like for a local file *) + +type + TReadWriteFunc = function(opaque: Pointer; buf: PByteArray; buf_size: cint): cint; cdecl; + TSeekFunc = function(opaque: Pointer; offset: cint64; whence: cint): cint64; cdecl; + Tcallback = function(p: pointer): cint; cdecl; + +type +(** + * Callback for checking whether to abort blocking functions. + * AVERROR_EXIT is returned in this case by the interrupted + * function. During blocking operations, callback is called with + * opaque as parameter. If the callback returns 1, the + * blocking operation will be aborted. + * + * No members can be added to this struct without a major bump, if + * new elements have been added after this struct in AVFormatContext + * or AVIOContext. + *) + PAVIOInterruptCB = ^TAVIOInterruptCB; + TAVIOInterruptCB = record + callback: Tcallback; + opaque: pointer; + end; (*TAVIOInterruptCB*) + + (** + * Directory entry types. + *) + TAVIODirEntryType = ( + AVIO_ENTRY_UNKNOWN, + AVIO_ENTRY_BLOCK_DEVICE, + AVIO_ENTRY_CHARACTER_DEVICE, + AVIO_ENTRY_DIRECTORY, + AVIO_ENTRY_NAMED_PIPE, + AVIO_ENTRY_SYMBOLIC_LINK, + AVIO_ENTRY_SOCKET, + AVIO_ENTRY_FILE, + AVIO_ENTRY_SERVER, + AVIO_ENTRY_SHARE, + AVIO_ENTRY_WORKGROUP + ); + + + (** + * Describes single entry of the directory. + * + * Only name and type fields are guaranteed be set. + * Rest of fields are protocol or/and platform dependent and might be unknown. + *) + PPAVIODirEntry = ^PAVIODirEntry; + PAVIODirEntry = ^TAVIODirEntry; + TAVIODirEntry = record + name: PAnsiChar; (**< Filename *) + type_: cint; (**< Type of the entry *) + utf8: cint; (**< Set to 1 when name is encoded with UTF-8, 0 otherwise. + Name can be encoded with UTF-8 even though 0 is set. *) + size: cint64; (**< File size in bytes, -1 if unknown. *) + modification_timestamp: cint64; (**< Time of last modification in microseconds since unix + epoch, -1 if unknown. *) + access_timestamp: cint64; (**< Time of last access in microseconds since unix epoch, + -1 if unknown. *) + status_change_timestamp: cint64; (**< Time of last status change in microseconds since unix + epoch, -1 if unknown. *) + user_id: cint64; (**< User ID of owner, -1 if unknown. *) + group_id: cint64; (**< Group ID of owner, -1 if unknown. *) + filemode: cint64; (**< Unix file mode, -1 if unknown. *) + end; + + PPAVIODirContext = ^PAVIODirContext; + PAVIODirContext = ^TAVIODirContext; + TAVIODirContext = record + url_context: pointer; + (** struct URLContext *url_context; *) + end; + +(** + * Bytestream IO Context. + * New fields can be added to the end with minor version bumps. + * Removal, reordering and changes to existing fields require a major + * version bump. + * sizeof(AVIOContext) must not be used outside libav*. + * + * @note None of the function pointers in AVIOContext should be called + * directly, they should only be set by the client application + * when implementing custom I/O. Normally these are set to the + * function pointers specified in avio_alloc_context() + *) + PPAVIOContext = ^PAVIOContext; + PAVIOContext = ^TAVIOContext; + TAVIOContext = record + (** + * A class for private options. + * + * If this AVIOContext is created by avio_open2(), av_class is set and + * passes the options down to protocols. + * + * If this AVIOContext is manually allocated, then av_class may be set by + * the caller. + * + * warning -- this field can be NULL, be sure to not pass this AVIOContext + * to any av_opt_* functions in that case. + *) + av_class: {const} PAVClass; + buffer: PByteArray; (**< Start of the buffer. *) + buffer_size: cint; (**< Maximum buffer size *) + buf_ptr: PByteArray; (**< Current position in the buffer *) + buf_end: PByteArray; (**< End of the data, may be less than + buffer+buffer_size if the read function returned + less data than requested, e.g. for streams where + no more data has been received yet. *) + opaque: pointer; (**< A private pointer, passed to the read/write/seek/... + functions. *) + read_packet: TReadWriteFunc; + write_packet: TReadWriteFunc; + seek: TSeekFunc; + pos: cint64; (**< position in the file of the current buffer *) + must_flush: cint; (**< true if the next seek should flush *) + eof_reached: cint; (**< true if eof reached *) + write_flag: cint; (**< true if open for writing *) + max_packet_size: cint; + checksum: culong; + checksum_ptr: PByteArray; + update_checksum: function (checksum: culong; buf: {const} PAnsiChar; size: cuint): culong; cdecl; + error: cint; (**< contains the error code or 0 if no error happened *) + (** + * Pause or resume playback for network streaming protocols - e.g. MMS. + *) + read_pause: function(opaque: Pointer; pause: cint): cint; cdecl; + (** + * Seek to a given timestamp in stream with the specified stream_index. + * Needed for some network streaming protocols which don't support seeking + * to byte position. + *) + read_seek: function(opaque: Pointer; stream_index: cint; + timestamp: cint64; flags: cint): cint64; cdecl; + (** + * A combination of AVIO_SEEKABLE_ flags or 0 when the stream is not seekable. + *) + seekable: cint; + + (** + * max filesize, used to limit allocations + * This field is internal to libavformat and access from outside is not allowed. + *) + maxsize: cint64; + + (** + * avio_read and avio_write should if possible be satisfied directly + * instead of going through a buffer, and avio_seek will always + * call the underlying seek function directly. + *) + direct: cint; + + (** + * Bytes read statistic + * This field is internal to libavformat and access from outside is not allowed. + *) + bytes_read: cint64; + + (** + * seek statistic + * This field is internal to libavformat and access from outside is not allowed. + *) + seek_count: cint; + + (** + * writeout statistic + * This field is internal to libavformat and access from outside is not allowed. + *) + writeout_count: cint; + + (** + * Original buffer size + * used internally after probing and ensure seekback to reset the buffer size + * This field is internal to libavformat and access from outside is not allowed. + *) + orig_buffer_size: cint; + end; + +(* unbuffered I/O *) + +(** + * Return AVIO_* access flags corresponding to the access permissions + * of the resource in url, or a negative value corresponding to an + * AVERROR code in case of failure. The returned access flags are + * masked by the value in flags. + * + * @note This function is intrinsically unsafe, in the sense that the + * checked resource may change its existence or permission status from + * one call to another. Thus you should not trust the returned value, + * unless you are sure that no other processes are accessing the + * checked resource. + *) +function avio_check(url: {const} PAnsiChar; flags: cint): cint; + cdecl; external av__format; + +(** + * Open directory for reading. + * + * @param s directory read context. Pointer to a NULL pointer must be passed. + * @param url directory to be listed. + * @param options A dictionary filled with protocol-private options. On return + * this parameter will be destroyed and replaced with a dictionary + * containing options that were not found. May be NULL. + * @return >=0 on success or negative on error. + *) +function avio_open_dir(s: PPAVIODirContext; url: {const} PAnsiChar; options: PPAVDictionary): cint; + cdecl; external av__format; + +(** + * Get next directory entry. + * + * Returned entry must be freed with avio_free_directory_entry(). In particular + * it may outlive AVIODirContext. + * + * @param s directory read context. + * @param[out] next next entry or NULL when no more entries. + * @return >=0 on success or negative on error. End of list is not considered an + * error. + *) +function avio_read_dir(s: PAVIODirContext; next: PPAVIODirEntry): cint; + cdecl; external av__format; + +(** + * Close directory. + * + * @note Entries created using avio_read_dir() are not deleted and must be + * freeded with avio_free_directory_entry(). + * + * @param s directory read context. + * @return >=0 on success or negative on error. + *) +function avio_close_dir(s: PPAVIODirContext): cint; + cdecl; external av__format; + +(** + * Free entry allocated by avio_read_dir(). + * + * @param entry entry to be freed. + *) +procedure avio_free_directory_entry(entry: PPAVIODirEntry); + cdecl; external av__format; + +(** + * Allocate and initialize an AVIOContext for buffered I/O. It must be later + * freed with av_free(). + * + * @param buffer Memory block for input/output operations via AVIOContext. + * The buffer must be allocated with av_malloc() and friends. + * It may be freed and replaced with a new buffer by libavformat. + * AVIOContext.buffer holds the buffer currently in use, + * which must be later freed with av_free(). + * @param buffer_size The buffer size is very important for performance. + * For protocols with fixed blocksize it should be set to this blocksize. + * For others a typical size is a cache page, e.g. 4kb. + * @param write_flag Set to 1 if the buffer should be writable, 0 otherwise. + * @param opaque An opaque pointer to user-specific data. + * @param read_packet A function for refilling the buffer, may be NULL. + * @param write_packet A function for writing the buffer contents, may be NULL. + * The function may not change the input buffers content. + * @param seek A function for seeking to specified byte position, may be NULL. + * + * @return Allocated AVIOContext or NULL on failure. + *) +function avio_alloc_context( + buffer: PAnsiChar; + buffer_size: cint; + write_flag: cint; + opaque: Pointer; + read_packet: TReadWriteFunc; + write_packet: TReadWriteFunc; + seek: TSeekFunc): PAVIOContext; + cdecl; external av__format; + +procedure avio_w8(s: PAVIOContext; b: cint); + cdecl; external av__format; +procedure avio_write(s: PAVIOContext; buf: {const} PAnsiChar; size: cint); + cdecl; external av__format; +procedure avio_wl64(s: PAVIOContext; val: cuint64); + cdecl; external av__format; +procedure avio_wb64(s: PAVIOContext; val: cuint64); + cdecl; external av__format; +procedure avio_wl32(s: PAVIOContext; val: cuint); + cdecl; external av__format; +procedure avio_wb32(s: PAVIOContext; val: cuint); + cdecl; external av__format; +procedure avio_wl24(s: PAVIOContext; val: cuint); + cdecl; external av__format; +procedure avio_wb24(s: PAVIOContext; val: cuint); + cdecl; external av__format; +procedure avio_wl16(s: PAVIOContext; val: cuint); + cdecl; external av__format; +procedure avio_wb16(s: PAVIOContext; val: cuint); + cdecl; external av__format; + +(** + * Write a NULL-terminated string. + * @return number of bytes written. + *) +function avio_put_str(s: PAVIOContext; str: {const} PAnsiChar): cint; + cdecl; external av__format; + +(** + * Convert an UTF-8 string to UTF-16LE and write it. + * @param s the AVIOContext + * @param str NULL-terminated UTF-8 string + * + * @return number of bytes written. + *) +function avio_put_str16le(s: PAVIOContext; str: {const} PAnsiChar): cint; + cdecl; external av__format; + +(** + * Convert an UTF-8 string to UTF-16BE and write it. + * @param s the AVIOContext + * @param str NULL-terminated UTF-8 string + * + * @return number of bytes written. + *) +function avio_put_str16be(s: PAVIOContext; str: {const} PAnsiChar): cint; + cdecl; external av__format; + +const +(** + * Passing this as the "whence" parameter to a seek function causes it to + * return the filesize without seeking anywhere. Supporting this is optional. + * If it is not supported then the seek function will return <0. + *) + AVSEEK_SIZE = $10000; + +(** + * Oring this flag as into the "whence" parameter to a seek function causes it to + * seek by any means (like reopening and linear reading) or other normally unreasonable + * means that can be extremely slow. + * This may be ignored by the seek code. + *) + AVSEEK_FORCE = $20000; + +(** + * fseek() equivalent for AVIOContext. + * @return new position or AVERROR. + *) +function avio_seek(s: PAVIOContext; offset: cint64; whence: cint): cint64; + cdecl; external av__format; + +(** + * Skip given number of bytes forward + * @return new position or AVERROR. + *) +function avio_skip(s: PAVIOContext; offset: cint64): cint64; + cdecl; external av__format; + +{$IFDEF UNIX} +(** + * ftell() equivalent for AVIOContext. + * @return position or AVERROR. + *) +function avio_tell(s: PAVIOContext): cint64; {$IFDEF HasInline}inline;{$ENDIF} +{$ELSE} +{$ENDIF} + +(** + * Get the filesize. + * @return filesize or AVERROR + *) +function avio_size(s: PAVIOContext): cint64; + cdecl; external av__format; + +(** + * feof() equivalent for AVIOContext. + * @return non zero if and only if end of file + *) +function avio_feof(s: PAVIOContext): cint; + cdecl; external av__format; +{$IFDEF FF_API_URL_FEOF} +(** + * @deprecated use avio_feof() + *) +function url_feof(s: PAVIOContext): cint; + cdecl; external av__format; {attribute_deprecated} +{$ENDIF} + +(** @warning currently size is limited *) +function avio_printf(s: PAVIOContext; fmt: {const} PAnsiChar; args: array of const): cint; + cdecl; external av__format; + +(** + * Force flushing of buffered data. + * + * For write streams, force the buffered data to be immediately written to the output, + * without to wait to fill the internal buffer. + * + * For read streams, discard all currently buffered data, and advance the + * reported file position to that of the underlying stream. This does not + * read new data, and does not perform any seeks. + *) +procedure avio_flush(s: PAVIOContext); + cdecl; external av__format; + +(** + * Read size bytes from AVIOContext into buf. + * @return number of bytes read or AVERROR + *) +function avio_read(s: PAVIOContext; buf: Pbyte; size: cint): cint; + cdecl; external av__format; + +(** + * @name Functions for reading from AVIOContext + * @ + * + * @note return 0 if EOF, so you cannot use it if EOF handling is + * necessary + *) +function avio_r8(s: PAVIOContext): cint; + cdecl; external av__format; + +function avio_rl16(s: PAVIOContext): cuint; + cdecl; external av__format; + +function avio_rl24(s: PAVIOContext): cuint; + cdecl; external av__format; + +function avio_rl32(s: PAVIOContext): cuint; + cdecl; external av__format; + +function avio_rl64(s: PAVIOContext): cuint64; + cdecl; external av__format; + +function avio_rb16(s: PAVIOContext): cuint; + cdecl; external av__format; + +function avio_rb24(s: PAVIOContext): cuint; + cdecl; external av__format; + +function avio_rb32(s: PAVIOContext): cuint; + cdecl; external av__format; + +function avio_rb64(s: PAVIOContext): cuint64; + cdecl; external av__format; + +(** + * @ + *) +(** + * Read a string from pb into buf. The reading will terminate when either + * a NULL character was encountered, maxlen bytes have been read, or nothing + * more can be read from pb. The result is guaranteed to be NULL-terminated, it + * will be truncated if buf is too small. + * Note that the string is not interpreted or validated in any way, it + * might get truncated in the middle of a sequence for multi-byte encodings. + * + * @return number of bytes read (is always <= maxlen). + * If reading ends on EOF or error, the return value will be one more than + * bytes actually read. + *) +function avio_get_str(pb: PAVIOContext; maxlen: cint; buf: PAnsiChar; buflen: cint): cint; + cdecl; external av__format; + +(** + * Read a UTF-16 string from pb and convert it to UTF-8. + * The reading will terminate when either a null or invalid character was + * encountered or maxlen bytes have been read. + * @return number of bytes read (is always <= maxlen) + *) +function avio_get_str16le(pb: PAVIOContext; maxlen: cint; buf: PAnsiChar; buflen: cint): cint; + cdecl; external av__format; + +function avio_get_str16be(pb: PAVIOContext; maxlen: cint; buf: PAnsiChar; buflen: cint): cint; + cdecl; external av__format; + +(** + * @name URL open modes + * The flags argument to avio_open must be one of the following + * constants, optionally ORed with other flags. + * @{ + *) +const + AVIO_FLAG_READ = 1; (**< read-only *) + AVIO_FLAG_WRITE = 2; (**< write-only *) + AVIO_FLAG_READ_WRITE = {(AVIO_FLAG_READ|AVIO_FLAG_WRITE)} 3; (**< read-write pseudo flag *) +(** + * @ + *) + +const +(** + * Use non-blocking mode. + * If this flag is set, operations on the context will return + * AVERROR(EAGAIN) if they can not be performed immediately. + * If this flag is not set, operations on the context will never return + * AVERROR(EAGAIN). + * Note that this flag does not affect the opening/connecting of the + * context. Connecting a protocol will always block if necessary (e.g. on + * network protocols) but never hang (e.g. on busy devices). + * Warning: non-blocking protocols is work-in-progress; this flag may be + * silently ignored. + *) + AVIO_FLAG_NONBLOCK = 8; + +(** + * Use direct mode. + * avio_read and avio_write should if possible be satisfied directly + * instead of going through a buffer, and avio_seek will always + * call the underlying seek function directly. + *) + AVIO_FLAG_DIRECT = $8000; + +(** + * Create and initialize a AVIOContext for accessing the + * resource indicated by url. + * @note When the resource indicated by url has been opened in + * read+write mode, the AVIOContext can be used only for writing. + * + * @param s Used to return the pointer to the created AVIOContext. + * In case of failure the pointed to value is set to NULL. + * @param flags flags which control how the resource indicated by url + * is to be opened + * @return 0 in case of success, a negative value corresponding to an + * AVERROR code in case of failure + *) +function avio_open(s: PPAVIOContext; url: {const} PAnsiChar; flags: cint): cint; + cdecl; external av__format; + +(** + * Create and initialize a AVIOContext for accessing the + * resource indicated by url. + * @note When the resource indicated by url has been opened in + * read+write mode, the AVIOContext can be used only for writing. + * + * @param s Used to return the pointer to the created AVIOContext. + * In case of failure the pointed to value is set to NULL. + * @param flags flags which control how the resource indicated by url + * is to be opened + * @param int_cb an interrupt callback to be used at the protocols level + * @param options A dictionary filled with protocol-private options. On return + * this parameter will be destroyed and replaced with a dict containing options + * that were not found. May be NULL. + * @return 0 in case of success, a negative value corresponding to an + * AVERROR code in case of failure + *) +function avio_open2(s: PPAVIOContext; {const} url: PAnsiChar; flags: cint; + {const} int_cb: PAVIOInterruptCB; options: PPAVDictionary): cint; + cdecl; external av__format; + +(** + * Close the resource accessed by the AVIOContext s and free it. + * This function can only be used if s was opened by avio_open(). + * + * The internal buffer is automatically flushed before closing the + * resource. + * + * @return 0 on success, an AVERROR < 0 on error. + * @see avio_close + *) +function avio_close(s: PAVIOContext): cint; + cdecl; external av__format; + +(** + * Close the resource accessed by the AVIOContext *s, free it + * and set the pointer pointing to it to NULL. + * This function can only be used if s was opened by avio_open(). + * + * The internal buffer is automatically flushed before closing the + * resource. + * + * @return 0 on success, an AVERROR < 0 on error. + * @see avio_close + *) +function avio_closep(s: PPAVIOContext): cint; + cdecl; external av__format; + +(** + * Open a write only memory stream. + * + * @param s new IO context + * @return zero if no error. + *) +function avio_open_dyn_buf(s: PPAVIOContext): cint; + cdecl; external av__format; + +(** + * Return the written size and a pointer to the buffer. The buffer + * must be freed with av_free(). + * Padding of FF_INPUT_BUFFER_PADDING_SIZE is added to the buffer. + * + * @param s IO context + * @param pbuffer pointer to a byte buffer + * @return the length of the byte buffer + *) +function avio_close_dyn_buf(s: PAVIOContext; var pbuffer: Pcuint8): cint; + cdecl; external av__format; + +(** + * Iterate through names of available protocols. + * + * @param opaque A private pointer representing current protocol. + * It must be a pointer to NULL on first iteration and will + * be updated by successive calls to avio_enum_protocols. + * @param output If set to 1, iterate over output protocols, + * otherwise over input protocols. + * + * @return A static string containing the name of current protocol or NULL + *) +function avio_enum_protocols(var opaque: Pointer; output: cint): {const} PAnsiChar; + cdecl; external av__format; + +(** + * Pause and resume playing - only meaningful if using a network streaming + * protocol (e.g. MMS). + * @param pause 1 for pause, 0 for resume + *) +function avio_pause(h: PAVIOContext; pause: cint): cint; + cdecl; external av__format; + +(** + * Seek to a given timestamp relative to some component stream. + * Only meaningful if using a network streaming protocol (e.g. MMS.). + * @param stream_index The stream index that the timestamp is relative to. + * If stream_index is (-1) the timestamp should be in AV_TIME_BASE + * units from the beginning of the presentation. + * If a stream_index >= 0 is used and the protocol does not support + * seeking based on component streams, the call will fail with ENOTSUP. + * @param timestamp timestamp in AVStream.time_base units + * or if there is no stream specified then in AV_TIME_BASE units. + * @param flags Optional combination of AVSEEK_FLAG_BACKWARD, AVSEEK_FLAG_BYTE + * and AVSEEK_FLAG_ANY. The protocol may silently ignore + * AVSEEK_FLAG_BACKWARD and AVSEEK_FLAG_ANY, but AVSEEK_FLAG_BYTE will + * fail with ENOTSUP if used and not supported. + * @return >= 0 on success + * @see AVInputFormat: : read_seek + *) +function avio_seek_time(h: PAVIOContext; stream_index: cint; + timestamp: cint64; flags: cint): cint64; + cdecl; external av__format; + +(* Avoid a warning. The header can not be included because it breaks c++. *) +type + PAVBPrint = ^TAVBPrint; + TAVBPrint = record + end; + +(** + * Read contents of h into print buffer, up to max_size bytes, or up to EOF. + * + * @return 0 for success (max_size bytes read or EOF reached), negative error + * code otherwise + *) +function avio_read_to_bprint(h: PAVIOContext; pb: PAVBPrint; max_size: size_t): cint; + cdecl; external av__format; + +implementation + +(** + * For SEEK_CUR on Windows + * values taken from stdio.h of C + *) +{$IFNDEF SEEK_SET} +const + SEEK_SET = 0; +{$ENDIF} + +{$IFNDEF SEEK_CUR} +const + SEEK_CUR = 1; +{$ENDIF} + +{$IFNDEF SEEK_END} +const + SEEK_END = 2; +{$ENDIF} + +function avio_tell(s: PAVIOContext): cint64; {$IFDEF HasInline}inline;{$ENDIF} +begin + Result := avio_seek(s, 0, SEEK_CUR); +end; + + +end. |