Class upisnd::ValueFd

Detailed Description

Takes care of managing the lifetime of the fd.

You may retrieve the fd value using get() or take ownership of it using take(). If you take the ownership, the ValueFd object will immediately forget about the fd, and you'll be responsible to close it yourself.

• #include <value_fd.h>

Public Functions

Type	Name
	ValueFd ()
	ValueFd (int fd) Creates a ValueFd from an existing fd, takes ownership of it, so it will close it in the destructor.
	~ValueFd ()
	ValueFd (const ValueFd & rhs) Copy constructor, duplicates the fd using F_DUPFD_CLOEXEC fcntl call.
ValueFd &	operator= (const ValueFd & rhs) Copy assignment operator, first it closes any valid fd it may have had, then duplicates the rhs fd using F_DUPFD_CLOEXEC fcntl call.
	ValueFd (ValueFd && rhs) Move constructor, moves take ownership of the fd.
ValueFd &	operator= (ValueFd && rhs) Move assignment operator, first it closes any valid fd it may have had, then assumes ownership of the rhs fd, invalidating the rhs object.
bool	isValid () const Returns true if the object holds a valid fd.
int	take () Returns the fd value, and won't close it in the destructor, transferring ownership.
int	get () const Returns the fd value for your use, but keeps ownership, and will close it upon destruction.
int	close () Closes the fd and forgets about it.
int	write (int value) Outputs a decimal number to the fd.
int	read (int * err=NULL) const

ValueFd [1/4]

upisnd::ValueFd::ValueFd () 

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ValueFd [2/4]

Creates a ValueFd from an existing fd, takes ownership of it, so it will close it in the destructor.

explicit upisnd::ValueFd::ValueFd (
    int fd
) 

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~ValueFd

upisnd::ValueFd::~ValueFd () 

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ValueFd [3/4]

Copy constructor, duplicates the fd using F_DUPFD_CLOEXEC fcntl call.

upisnd::ValueFd::ValueFd (
    const ValueFd & rhs
) 

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operator=

Copy assignment operator, first it closes any valid fd it may have had, then duplicates the rhs fd using F_DUPFD_CLOEXEC fcntl call.

ValueFd & upisnd::ValueFd::operator= (
    const ValueFd & rhs
) 

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ValueFd [4/4]

Move constructor, moves take ownership of the fd.

upisnd::ValueFd::ValueFd (
    ValueFd && rhs
) 

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operator=

Move assignment operator, first it closes any valid fd it may have had, then assumes ownership of the rhs fd, invalidating the rhs object.

ValueFd & upisnd::ValueFd::operator= (
    ValueFd && rhs
) 

---

isValid

Returns true if the object holds a valid fd.

bool upisnd::ValueFd::isValid () const

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take

Returns the fd value, and won't close it in the destructor, transferring ownership.

int upisnd::ValueFd::take () 

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get

Returns the fd value for your use, but keeps ownership, and will close it upon destruction.

int upisnd::ValueFd::get () const

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close

Closes the fd and forgets about it.

int upisnd::ValueFd::close () 

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write

Outputs a decimal number to the fd.

int upisnd::ValueFd::write (
    int value
) 

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read

int upisnd::ValueFd::read (
    int * err=NULL
) const

Reads a decimal number from the fd and returns it as integer.

Parameters:

• err If not NULL, will be set to the errno value if the read failed, 0 otherwise.

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