Class
FileRepresents a file.
Represents a file.
All Subcl's | AsyncFile, SyncFile |
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Defined in | <seqan/file.h> |
Signature |
template <[typename TSpec]>
class File<TSpec>;
|
Template Parameters
TSpec |
Specializing type. Default: Async<>. |
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Interface Function Overview
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bool asyncReadAt(file, memPtr, count, fileOfs, request);
Asynchronously loads records from a specific position in a file. -
bool asyncWriteAt(file, memPtr, count, fileOfs, request);
Asynchronously writes records to a specific position in a file. -
bool cancel(file, request);
Cancels an asynchronous request. -
bool close(file);
Close a file. -
void flush(file);
Waits for all open requests to complete. -
TSize length(file);
Return the file size. -
bool open(file, fileName, openMode);
Opens a file, stream, or persistent string. -
bool openTemp(file);
Opens a temporary file. -
bool read(file, memPtr, count);
Loads record from a file. -
bool readAt(file, memPtr, count, fileOfs);
Loads records from a specific position in a file. -
void resize(file, newLength);
A file object. -
void rewind(file);
Sets the current file pointer to the beginning of a file. -
TPosition seek(file, fileOfs[, origin]);
Changes the current file pointer. -
bool setEof(file);
Sets the file end to the current pointer. -
TPosition tell(file);
Gets the current file pointer. -
bool waitFor(request[, timeout]);
Waits for an asynchronous request to complete. -
bool write(file, memPtr, count);
Saves records to a file. -
bool writeAt(file, memPtr, count, fileOfs);
Saves records to a specific position in a file.
Interface Functions Detail
bool asyncReadAt(file, memPtr, count, fileOfs, request);
Asynchronously loads records from a specific position in a file.
Parameters
file
|
The File object to read from. |
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memPtr
|
A pointer to the first destination record in memory. |
count
|
The amount of records to be read. |
fileOfs
|
The absolute file position in bytes measured from the beginning. |
request
|
Reference to a structure that will be associated with this asynchronous request. Type: AsyncRequest. |
Returns
bool |
true on success, false on failure. |
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Data Races
Thread safety unknown!
bool asyncWriteAt(file, memPtr, count, fileOfs, request);
Asynchronously writes records to a specific position in a file.
Parameters
file
|
The File object. |
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memPtr
|
A pointer to the first source record in memory. |
count
|
The amount of records to be written. |
fileOfs
|
The absolute file position in bytes measured form the beginning. |
request
|
Reference to a structure that will be associated with this asynchronous request. |
Returns
bool |
true on success, false on failure. |
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Data Races
Thread safety unknown!
bool cancel(file, request);
Cancels an asynchronous request.
Parameters
file
|
The File to cancel the request for. |
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request
|
Reference to an AsyncRequest object. Type: AsyncRequest. |
Returns
bool |
true on success, false on failure. |
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Data Races
Thread safety unknown!
bool close(file);
Close a file.
Parameters
file
|
The File object to close. |
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Returns
bool |
true on success, false on failure. |
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Data Races
Thread safety unknown!
void flush(file);
Waits for all open requests to complete.
Parameters
file
|
The File object to flush. |
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Data Races
Thread safety unknown!
TSize length(file);
Return the file size.
Parameters
file
|
The File object to query for its size. |
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Returns
TSize |
The file size measured in bytes. |
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Data Races
Thread safety unknown!
bool open(file, fileName, openMode);
Opens a file, stream, or persistent string.
Parameters
file
|
The File to open. |
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fileName
|
A char const * string containing the file name. |
openMode
|
Combination of flags defining how the file should be opened. See FileOpenMode for more details. Type: int. If you omit the OPEN_APPEND flag in write mode, the file will be cleared when opened. Default: OPEN_RDWR | OPEN_CREATE | OPEN_APPEND. |
Returns
bool |
true on success, false on failure. |
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Data Races
Thread safety unknown!
bool openTemp(file);
Opens a temporary file.
Parameters
file
|
The File object to open the temporary file. |
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Returns
bool |
true on success, false on failure. |
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bool |
true on success false on failure. |
Remarks
After closing this file will be deleted automatically. The openmode (see open) is OPEN_RDWR | OPEN_CREATE.
Data Races
Thread safety unknown!
bool read(file, memPtr, count);
Loads record from a file.
Parameters
file
|
The File object. |
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memPtr
|
A pointer to the first destination record in memory. |
count
|
The amount of records to be read. |
Returns
bool |
true on success, false on failure. |
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Remarks
The records are read from the position pointed to by the current file pointer (see seek).
Data Races
Thread safety unknown!
bool readAt(file, memPtr, count, fileOfs);
Loads records from a specific position in a file.
Parameters
file
|
The File object to read from. |
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memPtr
|
A pointer to the first destination record in memory. |
count
|
The amount of records to be read. |
fileOfs
|
The absolute file position in bytes measured from the beginning. |
Returns
bool |
true on success and false on failure. |
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Data Races
Thread safety unknown!
void resize(file, newLength);
A file object.
Parameters
file
|
The File object to resize. |
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newLength
|
The file size in bytes to resize to in bytes. |
Data Races
Thread safety unknown!
void rewind(file);
Sets the current file pointer to the beginning of a file.
Parameters
file
|
The file to reset the file pointer of. |
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Data Races
Thread safety unknown!
TPosition seek(file, fileOfs[, origin]);
Changes the current file pointer.
Parameters
file
|
The File object to seek in. |
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fileOfs
|
A file offset measured in bytes relative to origin. |
origin
|
Selects the origin from where to calculate the new position. One of SEEK_BEGIN, SEEK_CURRENT, and SEEK_END (origin is beginning, current pointer, end of the file). Default: SEEK_BEGIN. |
Returns
TPosition |
The new file position measured in bytes from the beginning. |
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Data Races
Thread safety unknown!
bool setEof(file);
Sets the file end to the current pointer.
Parameters
file
|
The File object to set the end of. |
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Returns
bool |
true on success, false on failure. |
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Data Races
Thread safety unknown!
TPosition tell(file);
Gets the current file pointer.
Parameters
file
|
The File object to query for the current position. |
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Returns
TPosition |
The current position in the file. |
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Data Races
Thread safety unknown!
bool waitFor(request[, timeout]);
Waits for an asynchronous request to complete.
Parameters
request
|
Reference to an AsyncRequest. |
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timeout
|
A timeout value in milliseconds. A value of 0 can be used to test for completion without waiting. Default: 0. |
Returns
bool |
true on completion, false on timeout. |
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Remarks
waitfor block sand suspends the calling thread process until request is completed or after timeout milliseconds.
Data Races
Thread safety unknown!
bool write(file, memPtr, count);
Saves records to a file.
Parameters
file
|
The File object. |
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memPtr
|
Pointer to the source for the data to write. |
count
|
The number of records to write. |
Returns
bool |
true on success, false on failure. |
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Remarks
The records are written at the position pointed to by the current file pointer (see seek).
Data Races
Thread safety unknown!
bool writeAt(file, memPtr, count, fileOfs);
Saves records to a specific position in a file.
Parameters
file
|
The File object to write to. |
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memPtr
|
Pointer to the memory to write. |
count
|
The amount of records to be written. |
fileOfs
|
The absolute file position in bytes measured from the beginning. |
Returns
bool |
true on success, false on failure. |
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Data Races
Thread safety unknown!