Provided by: libexplain-dev_1.4.D001-2_amd64 
NAME
explain_bind - explain bind(2) errors
SYNOPSIS
#include <libexplain/bind.h>
const char *explain_bind(int fildes, const struct sockaddr *sock_addr, int
sock_addr_size);
const char *explain_errno_bind(int errnum, int fildes, const struct sockaddr *sock_addr,
int sock_addr_size);
void explain_message_bind(char *message, int message_size, int fildes, const struct
sockaddr *sock_addr, int sock_addr_size);
void explain_message_errno_bind(char *message, int message_size, int errnum, int fildes,
const struct sockaddr *sock_addr, int sock_addr_size);
DESCRIPTION
These functions may be used to obtain explanations for errors returned by the bind(2)
system call.
explain_bind
const char *explain_bind(int fildes, const struct sockaddr *sock_addr, int
sock_addr_size);
The explain_bind function is used to obtain an explanation of an error returned by the
bind(2) system call. The least the message will contain is the value of strerror(errno),
but usually it will do much better, and indicate the underlying cause in more detail.
The errno global variable will be used to obtain the error value to be decoded.
This function is intended to be used in a fashion similar to the following example:
if (bind(fildes, sock_addr, sock_addr_size) < 0)
{
fprintf(stderr, "%s\n",
explain_bind(fildes, sock_addr, sock_addr_size));
exit(EXIT_FAILURE);
}
The above code example is available pre‐packaged as the explain_bind_or_die(3) function.
fildes The original fildes, exactly as passed to the bind(2) system call.
sock_addr
The original sock_addr, exactly as passed to the bind(2) system call.
sock_addr_size
The original sock_addr_size, exactly as passed to the bind(2) system call.
Returns:
The message explaining the error. This message buffer is shared by all libexplain
functions which do not supply a buffer in their argument list. This will be
overwritten by the next call to any libexplain function which shares this buffer,
including other threads.
Note: This function is not thread safe, because it shares a return buffer across all
threads, and many other functions in this library.
explain_errno_bind
const char *explain_errno_bind(int errnum, int fildes, const struct sockaddr *sock_addr,
int sock_addr_size);
The explain_errno_bind function is used to obtain an explanation of an error returned by
the bind(2) system call. The least the message will contain is the value of
strerror(errnum), but usually it will do much better, and indicate the underlying cause in
more detail.
This function is intended to be used in a fashion similar to the following example:
if (bind(fildes, sock_addr, sock_addr_size) < 0)
{
int err = errno;
fprintf(stderr, "%s\n", explain_errno_bind(err,
fildes, sock_addr, sock_addr_size));
exit(EXIT_FAILURE);
}
The above code example is available pre‐packaged as the explain_bind_or_die(3) function.
errnum The error value to be decoded, usually obtained from the errno global variable
just before this function is called. This is necessary if you need to call any
code between the system call to be explained and this function, because many libc
functions will alter the value of errno.
fildes The original fildes, exactly as passed to the bind(2) system call.
sock_addr
The original sock_addr, exactly as passed to the bind(2) system call.
sock_addr_size
The original sock_addr_size, exactly as passed to the bind(2) system call.
Returns:
The message explaining the error. This message buffer is shared by all libexplain
functions which do not supply a buffer in their argument list. This will be
overwritten by the next call to any libexplain function which shares this buffer,
including other threads.
Note: This function is not thread safe, because it shares a return buffer across all
threads, and many other functions in this library.
explain_message_bind
void explain_message_bind(char *message, int message_size, int fildes, const struct
sockaddr *sock_addr, int sock_addr_size);
The explain_message_bind function may be used to obtain an explanation of an error
returned by the bind(2) system call. The least the message will contain is the value of
strerror(errno), but usually it will do much better, and indicate the underlying cause in
more detail.
The errno global variable will be used to obtain the error value to be decoded.
This function is intended to be used in a fashion similar to the following example:
if (bind(fildes, sock_addr, sock_addr_size) < 0)
{
char message[3000];
explain_message_bind(message, sizeof(message),
fildes, sock_addr, sock_addr_size);
fprintf(stderr, "%s\n", message);
exit(EXIT_FAILURE);
}
The above code example is available pre‐packaged as the explain_bind_or_die(3) function.
message The location in which to store the returned message. If a suitable message return
buffer is supplied, this function is thread safe.
message_size
The size in bytes of the location in which to store the returned message.
fildes The original fildes, exactly as passed to the bind(2) system call.
sock_addr
The original sock_addr, exactly as passed to the bind(2) system call.
sock_addr_size
The original sock_addr_size, exactly as passed to the bind(2) system call.
explain_message_errno_bind
void explain_message_errno_bind(char *message, int message_size, int errnum, int fildes,
const struct sockaddr *sock_addr, int sock_addr_size);
The explain_message_errno_bind function may be used to obtain an explanation of an error
returned by the bind(2) system call. The least the message will contain is the value of
strerror(errnum), but usually it will do much better, and indicate the underlying cause in
more detail.
This function is intended to be used in a fashion similar to the following example:
if (bind(fildes, sock_addr, sock_addr_size) < 0)
{
int err = errno;
char message[3000];
explain_message_errno_bind(message, sizeof(message), err,
fildes, sock_addr, sock_addr_size);
fprintf(stderr, "%s\n", message);
exit(EXIT_FAILURE);
}
The above code example is available pre‐packaged as the explain_bind_or_die(3) function.
message The location in which to store the returned message. If a suitable message return
buffer is supplied, this function is thread safe.
message_size
The size in bytes of the location in which to store the returned message.
errnum The error value to be decoded, usually obtained from the errno global variable
just before this function is called. This is necessary if you need to call any
code between the system call to be explained and this function, because many libc
functions will alter the value of errno.
fildes The original fildes, exactly as passed to the bind(2) system call.
sock_addr
The original sock_addr, exactly as passed to the bind(2) system call.
sock_addr_size
The original sock_addr_size, exactly as passed to the bind(2) system call.
SEE ALSO
bind(2) bind a name to a socket
explain_bind_or_die(3)
bind a name to a socket and report errors
COPYRIGHT
libexplain version 1.4
Copyright (C) 2008 Peter Miller
explain_bind(3)