errno

FBB::Errno(3bobcat)               Error handler              FBB::Errno(3bobcat)



NAME
       FBB::Errno - Throwable objects handling error conditions

SYNOPSIS
       #include <bobcat/errno>
       Linking option: -lbobcat

DESCRIPTION
       FBB::Errno objects may be thrown in exceptions.  As they are also
       std::ostringstream objects, information may be inserted into them.
       Facilitities are offered to insert information into, and to throw
       anonymous FBB::Errno objects.

       Errno exceptions may be thrown by several Bobcat classes. These classes
       are Arg, ArgConfig, BigInt, Cidr, ClientSocket, CmdFinder, CmdFinderBase,
       ConfigFile, DateTime, DecryptBuf, DigestBuf, EncryptBuf, Fork,
       GetHostent, Glob, HMacBuf, Hostname, InetAddress, level,
       LocalClientSocket, LocalServerSocket, LocalSocketBase, Log, MailHeaders,
       Mbuf, Milter, Mstream, OFoldStream, OFoldStreambuf, OneKey, Pattern,
       Pipe, Process, Redirector, Selector, ServerSocket, SocketBase, Stat,
       TempStream, User, Xpointer

NAMESPACE
       FBB
       All constructors, members, operators and manipulators, mentioned in this
       man-page, are defined in the namespace FBB.

INHERITS FROM
       std::ostringstream, std::exception

CONSTRUCTORS
       o      Errno():
              This constructor stores the current system errno value and its
              textual interpretation. No textual errno conversion is stored if
              errno equals 0.

       o      Errno(char const *prefix):
              This constructor stores the current system errno value. To this,
              the textual interpretation of errno is added unless errno equals
              0. If, in this situation, prefix is a non-empty string, the text :
              is first appended to the prefix.

       o      Errno(int errnr, char const *text = 0):
              This constructor stores the provided errnr value, and the text
              text. The text argument may be omitted or empty, in which case no
              text will be prefixed to any additionally inserted information.
              With this version of FBB::Errno, no :  is added to a non-empty
              text argument.  The copy constructor is available.

MEMBER FUNCTIONS
       All members of std::ostringstream and   std::exception are available, as
       FBB::Errno inherits from these classes.

       o      char const *why() const:
              Returns the initialized and inserted text. No separators are
              inserted by the FBB::Errno object between the initializatin text
              and any text inserted later. If separators are required, the user
              of the FBB::Errno object must insert these explicitly. The same
              text is returned by char const *what() const, which is part of
              std::exception’s interface.

       o      int which() const:
              Returns the internally stored errno value: either the system-errno
              value, or the value provided by the third constructor.


OVERLOADED OPERATORS
       o      Errno const &operator<<(Errno const &in, Type const &t):
              This overloaded insertion operator can be used to insert values of
              any type that can also be inserted into an ostringstream object.
              It is implemented as a template, with the generic Type
              representing the type of the value to be inserted.  The overloaded
              assignment operator is not available.

STATIC MEMBERS
       The following convenience functions can be used for controlled opening of
       std::istream, std::ostream and std::fstream objects. If opening fails an
       FBB::Errno(1) exception is thrown containing a short message stating that
       the named stream could not be opened. If the stream was already open it
       is closed first.

       o      static void open(std::ifstream &in, std::string const &name,
              std::ios::openmode mode = std::ios::in):
              Convenience function opening the object ifstream in refers to.

       o      static void open(std::ofstream &out, std::string const &name,
              std::ios::openmode mode = std::ios::out):
              Convenience function opening (creating) the object ofstream out
              refers to.

       o      static void open(std::fstream &out, std::string const &name,
              std::ios::openmode mode):
              Convenience function opening the object fstream out refers to.


EXAMPLE
       The following example shows the normal use of the manipulators:

           if (exceptionalCondition)
               throw FBB::Errno(1, "Failure") << ": Exceptional condition occurred";



FILES
       bobcat/errno - defines the class interface

SEE ALSO
       bobcat(7)

BUGS
       None Reported.

DISTRIBUTION FILES
       o      bobcat_3.14.00-x.dsc: detached signature;

       o      bobcat_3.14.00-x.tar.gz: source archive;

       o      bobcat_3.14.00-x_i386.changes: change log;

       o      libbobcat1_3.14.00-x_*.deb: debian package holding the libraries;

       o      libbobcat1-dev_3.14.00-x_*.deb: debian package holding the
              libraries, headers and manual pages;

       o      http://sourceforge.net/projects/bobcat: public archive location;


BOBCAT
       Bobcat is an acronym of `Brokken’s Own Base Classes And Templates’.

COPYRIGHT
       This is free software, distributed under the terms of the GNU General
       Public License (GPL).

AUTHOR
       Frank B. Brokken (f.b.brokken@rug.nl).

libbobcat-dev_3.14.00-x.tar.gz      2005-2013                FBB::Errno(3bobcat)