Content-type: text/html Man page of getpeername

getpeername

Section: System Calls (2)
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NAME

getpeername - Gets the name of the peer socket  

SYNOPSIS

#include <sys/socket.h>

int getpeername (        int socket,
       struct sockaddr *address,
       size_t *address_len );

[POSIX]  The definition of the getpeername() function in POSIX.1g Draft 6.6 uses a socklen_t data type instead of a size_t data type as specified in XNS4.0 (the previous definition).

[DIGITAL]  The following definition of the getpeername() function does not conform to current standards and is supported only for backward compatibility (see standards(5)):

int getpeername (        int socket,
       struct sockaddr *address,
       int *address_len );

 

STANDARDS

Interfaces documented on this reference page conform to industry standards as follows:

getpeername(): XNS4.0

The getpeername function also supports POSIX.1g Draft 6.6.

Refer to the standards(5) reference page for more information about industry standards and associated tags.  

PARAMETERS

Specifies the descriptor number of a connected socket. Points to a sockaddr structure, the format of which is determined by the domain and by the behavior requested for the socket. The sockaddr structure is an overlay for a sockaddr_in or sockaddr_un structure, depending on which of the supported address families is active.

[DIGITAL]   If the compile-time option _SOCKADDR_LEN is defined before the sys/socket.h header file is included, the sockaddr structure takes 4.4BSD behavior, with a field for specifying the length of the socket address. Otherwise, the default 4.3BSD sockaddr structure is used, with the length of the socket address assumed to be 14 bytes or less.
If _SOCKADDR_LEN is defined, the 4.3BSD sockaddr structure is defined with the name osockaddr. Specifies the length of the sockaddr structure pointed to by the address parameter.
 

DESCRIPTION

The getpeername() function retrieves the name of the peer socket connected to the specified socket.

A process created by another process can inherit open sockets, but may need to identify the addresses of the sockets it has inherited. The getpeername() function allows a process to retrieve the address of the peer socket at the remote end of the socket connection.  

NOTES

The getpeername() function operates only on connected sockets.

A process can use the getsockname() function to retrieve the local address of a socket.

[DIGITAL]  When compiled in the X/Open UNIX environment or the POSIX.1g socket environment, calls to the getpeername() function are internally renamed by prepending _E to the function name. When you are debugging a module that includes the getpeername() function and for which _XOPEN_SOURCE_EXTENDED or _POSIX_PII_SOCKET has been defined, use _Egetpeername to refer to the getpeername() call. See standards(5) for further information.  

RETURN VALUES

Upon successful completion, a value of 0 (zero) is returned and the address parameter holds the address of the peer socket. If the getpeername() function fails, a value of -1 is returned and errno is set to indicate the error.  

ERRORS

If the getpeername() function fails, errno may be set to one of the following values: The socket parameter is not valid. The address or address_len parameter is not in a writable part of the user address space. The socket has been shut down. Insufficient resources were available in the system to complete the call. The socket is not connected. The socket parameter refers to a file, not a socket. The operation is not supported for the socket protocol.  

RELATED INFORMATION

Functions: accept(2), bind(2), getsockname(2), socket(2).

Standards: standards(5). delim off


 

Index

NAME
SYNOPSIS
STANDARDS
PARAMETERS
DESCRIPTION
NOTES
RETURN VALUES
ERRORS
RELATED INFORMATION

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Time: 02:40:18 GMT, October 02, 2010