FreeBSD manual
download PDF document: bind.2.pdf
BIND(2) FreeBSD System Calls Manual BIND(2)
NAME
bind - assign a local protocol address to a socket
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/socket.h>
int
bind(int s, const struct sockaddr *addr, socklen_t addrlen);
DESCRIPTION
The bind() system call assigns the local protocol address to a socket.
When a socket is created with socket(2) it exists in an address family
space but has no protocol address assigned. The bind() system call
requests that addr be assigned to the socket.
NOTES
Binding an address in the UNIX domain creates a socket in the file system
that must be deleted by the caller when it is no longer needed (using
unlink(2)).
The rules used in address binding vary between communication domains.
Consult the manual entries in section 4 for detailed information.
For maximum portability, you should always zero the socket address
structure before populating it and passing it to bind().
RETURN VALUES
The bind() function returns the value 0 if successful; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORS
The bind() system call will fail if:
[EAGAIN] Kernel resources to complete the request are
temporarily unavailable.
[EBADF] The s argument is not a valid descriptor.
[EINVAL] The socket is already bound to an address, and the
protocol does not support binding to a new address; or
the socket has been shut down.
[EINVAL] The addrlen argument is not a valid length for the
address family.
[ENOTSOCK] The s argument is not a socket.
[EADDRNOTAVAIL] The specified address is not available from the local
machine.
[EADDRINUSE] The specified address is already in use.
[EAFNOSUPPORT] Addresses in the specified address family cannot be
The following errors are specific to binding addresses in the UNIX
domain.
[ENOTDIR] A component of the path prefix is not a directory.
[ENAMETOOLONG]
A component of a pathname exceeded 255 characters, or an
entire path name exceeded 1023 characters.
[ENOENT] A prefix component of the path name does not exist.
[ELOOP] Too many symbolic links were encountered in translating the
pathname.
[EIO] An I/O error occurred while making the directory entry or
allocating the inode.
[EINTEGRITY]
Corrupted data was detected while reading from the file
system.
[EROFS] The name would reside on a read-only file system.
[EISDIR] An empty pathname was specified.
SEE ALSO
connect(2), getsockname(2), listen(2), socket(2)
HISTORY
The bind() system call appeared in 4.2BSD.
FreeBSD 14.0-RELEASE-p11 March 30, 2020 FreeBSD 14.0-RELEASE-p11