| libpqxx
    4.0.1
    | 
Accessor for large object's contents. More...
#include <largeobject.hxx>
 
  
 | Public Types | |
| typedef long | off_type | 
| typedef size_type | pos_type | 
| typedef std::ios::openmode | openmode | 
| Open mode: in,out(can be combined with the "or" operator) | |
| typedef std::ios::seekdir | seekdir | 
| Seek direction: beg,cur,end. | |
| typedef long | size_type | 
| Public Member Functions | |
| largeobjectaccess (dbtransaction &T, openmode mode=std::ios::in|std::ios::out) | |
| Create new large object and open it. | |
| largeobjectaccess (dbtransaction &T, oid O, openmode mode=std::ios::in|std::ios::out) | |
| Open large object with given oid. | |
| largeobjectaccess (dbtransaction &T, largeobject O, openmode mode=std::ios::in|std::ios::out) | |
| Open given large object. | |
| largeobjectaccess (dbtransaction &T, const std::string &File, openmode mode=std::ios::in|std::ios::out) | |
| Import large object from a local file and open it. | |
| ~largeobjectaccess () throw () | |
| void | to_file (const std::string &File) const | 
| Export large object's contents to a local file. | |
| High-level access to object contents | |
| void | write (const char Buf[], size_type Len) | 
| Write data to large object. | |
| void | write (const std::string &Buf) | 
| Write string to large object. | |
| size_type | read (char Buf[], size_type Len) | 
| Read data from large object. | |
| size_type | seek (size_type dest, seekdir dir) | 
| Seek in large object's data stream. | |
| size_type | tell () const | 
| Report current position in large object's data stream. | |
| Low-level access to object contents | |
| These functions provide a more "C-like" access interface, returning special values instead of throwing exceptions on error. These functions are generally best avoided in favour of the high-level access functions, which behave more like C++ functions should. | |
| pos_type | cseek (off_type dest, seekdir dir) throw () | 
| Seek in large object's data stream. | |
| off_type | cwrite (const char Buf[], size_type Len) throw () | 
| Write to large object's data stream. | |
| off_type | cread (char Buf[], size_type Len) throw () | 
| Read from large object's data stream. | |
| pos_type | ctell () const throw () | 
| Report current position in large object's data stream. | |
| Error/warning output | |
| void | process_notice (const std::string &) throw () | 
| Issue message to transaction's notice processor. | |
| Additional Inherited Members | |
|  Private Types inherited from pqxx::largeobject | |
| typedef long | size_type | 
|  Private Member Functions inherited from pqxx::largeobject | |
| largeobject () throw () | |
| Refer to a nonexistent large object (similar to what a null pointer does) | |
| largeobject (dbtransaction &T) | |
| Create new large object. | |
| largeobject (oid O) throw () | |
| Wrap object with given oid. | |
| largeobject (dbtransaction &T, const std::string &File) | |
| Import large object from a local file. | |
| largeobject (const largeobjectaccess &O) throw () | |
| Take identity of an opened large object. | |
| oid | id () const throw () | 
| Object identifier. | |
| void | to_file (dbtransaction &T, const std::string &File) const | 
| Export large object's contents to a local file. | |
| void | remove (dbtransaction &T) const | 
| Delete large object from database. | |
| bool | operator== (const largeobject &other) const | 
| Compare object identities. | |
| bool | operator!= (const largeobject &other) const | 
| Compare object identities. | |
| bool | operator<= (const largeobject &other) const | 
| Compare object identities. | |
| bool | operator>= (const largeobject &other) const | 
| Compare object identities. | |
| bool | operator< (const largeobject &other) const | 
| Compare object identities. | |
| bool | operator> (const largeobject &other) const | 
| Compare object identities. | |
| std::string | Reason (int err) const | 
Accessor for large object's contents.
| typedef long pqxx::largeobjectaccess::off_type | 
| typedef std::ios::openmode pqxx::largeobjectaccess::openmode | 
Open mode: in, out (can be combined with the "or" operator) 
According to the C++ standard, these should be in std::ios_base. We take them from std::ios instead, which should be safe because it inherits the same definition, to accommodate gcc 2.95 & 2.96. 
| typedef std::ios::seekdir pqxx::largeobjectaccess::seekdir | 
Seek direction: beg, cur, end. 
According to the C++ standard, these should be in std::ios_base. We take them from std::ios instead, which should be safe because it inherits the same definition, to accommodate gcc 2.95 & 2.96. 
| typedef long pqxx::largeobject::size_type | 
| 
 | explicit | 
Create new large object and open it.
| T | Backend transaction in which the object is to be created | 
| mode | Access mode, defaults to ios_base::in | ios_base::out | 
References largeobjectaccess().
Referenced by largeobjectaccess().
| pqxx::largeobjectaccess::largeobjectaccess | ( | dbtransaction & | T, | 
| oid | O, | ||
| openmode | mode = std::ios::in | std::ios::out | ||
| ) | 
Open large object with given oid.
Convert combination of a transaction and object identifier into a large object identity. Does not affect the database.
| T | Transaction in which the object is to be accessed | 
| O | Object identifier for the given object | 
| mode | Access mode, defaults to ios_base::in | ios_base::out | 
References largeobjectaccess().
| pqxx::largeobjectaccess::largeobjectaccess | ( | dbtransaction & | T, | 
| largeobject | O, | ||
| openmode | mode = std::ios::in | std::ios::out | ||
| ) | 
Open given large object.
Open a large object with the given identity for reading and/or writing
| T | Transaction in which the object is to be accessed | 
| O | Identity for the large object to be accessed | 
| mode | Access mode, defaults to ios_base::in | ios_base::out | 
References largeobjectaccess().
| pqxx::largeobjectaccess::largeobjectaccess | ( | dbtransaction & | T, | 
| const std::string & | File, | ||
| openmode | mode = std::ios::in | std::ios::out | ||
| ) | 
Import large object from a local file and open it.
Creates a large object containing the data found in the given file.
| T | Backend transaction in which the large object is to be created | 
| File | A filename on the client program's filesystem | 
| mode | Access mode, defaults to ios_base::in | ios_base::out | 
References largeobjectaccess().
| pqxx::largeobjectaccess::~largeobjectaccess | ( | ) | throw () | 
| pqxx::largeobjectaccess::pos_type pqxx::largeobjectaccess::cread | ( | char | Buf[], | 
| size_type | Len | ||
| ) | throw () | 
Read from large object's data stream.
Does not throw exception in case of error; inspect return value and errno instead. 
| Buf | Area where incoming bytes should be stored | 
| Len | Number of bytes to read | 
| pqxx::largeobjectaccess::pos_type pqxx::largeobjectaccess::cseek | ( | off_type | dest, | 
| seekdir | dir | ||
| ) | throw () | 
Seek in large object's data stream.
Does not throw exception in case of error; inspect return value and errno instead. 
| dest | Offset to go to | 
| dir | Origin to which dest is relative: ios_base::beg (from beginning of the object), ios_base::cur (from current access position), or ios_base;:end (from end of object) | 
| pqxx::largeobjectaccess::pos_type pqxx::largeobjectaccess::ctell | ( | ) | const throw () | 
Report current position in large object's data stream.
Does not throw exception in case of error; inspect return value and errno instead. 
| pqxx::largeobjectaccess::pos_type pqxx::largeobjectaccess::cwrite | ( | const char | Buf[], | 
| size_type | Len | ||
| ) | throw () | 
Write to large object's data stream.
Does not throw exception in case of error; inspect return value and errno instead. 
| Buf | Data to write | 
| Len | Number of bytes to write | 
| void pqxx::largeobjectaccess::process_notice | ( | const std::string & | s | ) | throw () | 
Issue message to transaction's notice processor.
| pqxx::largeobjectaccess::size_type pqxx::largeobjectaccess::read | ( | char | Buf[], | 
| size_type | Len | ||
| ) | 
Read data from large object.
Throws an exception if an error occurs while reading.
| Buf | Location to store the read data in | 
| Len | Number of bytes to try and read | 
References pqxx::to_string().
| pqxx::largeobjectaccess::size_type pqxx::largeobjectaccess::seek | ( | size_type | dest, | 
| seekdir | dir | ||
| ) | 
Seek in large object's data stream.
Throws an exception if an error occurs.
| pqxx::largeobjectaccess::size_type pqxx::largeobjectaccess::tell | ( | ) | const | 
Report current position in large object's data stream.
Throws an exception if an error occurs.
| void pqxx::largeobjectaccess::to_file | ( | const std::string & | File | ) | const | 
Export large object's contents to a local file.
Writes the data stored in the large object to the given file.
| File | A filename on the client's filesystem | 
References pqxx::largeobject::to_file().
| void pqxx::largeobjectaccess::write | ( | const char | Buf[], | 
| size_type | Len | ||
| ) | 
Write data to large object.
If not all bytes could be written, an exception is thrown.
| Buf | Data to write | 
| Len | Number of bytes from Buf to write | 
References pqxx::to_string().
| void pqxx::largeobjectaccess::write | ( | const std::string & | Buf | ) |