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explain_connect(3)	   Library Functions Manual	    explain_connect(3)

NAME
       explain_connect - explain connect(2) errors

SYNOPSIS
       #include	<libexplain/connect.h>
       const   char   *explain_connect(int   fildes,   const  struct  sockaddr
       *serv_addr, int serv_addr_size);
       const char *explain_errno_connect(int errnum, int fildes, const	struct
       sockaddr	*serv_addr, int	serv_addr_size);
       void   explain_message_connect(char  *message,  int  message_size,  int
       fildes, const struct sockaddr *serv_addr, int serv_addr_size);
       void explain_message_errno_connect(char *message, int message_size, int
       errnum,	 int   fildes,	 const	 struct	  sockaddr   *serv_addr,   int
       serv_addr_size);

DESCRIPTION
       These functions may be used to obtain explanations for errors  returned
       by the connect(2) system	call.

   explain_connect
       const   char   *explain_connect(int   fildes,   const  struct  sockaddr
       *serv_addr, int serv_addr_size);

       The explain_connect function is used to obtain an explanation of	an er-
       ror returned by the connect(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  fol-
       lowing example:
	      if (connect(fildes, serv_addr, serv_addr_size) < 0)
	      {
		  fprintf(stderr, "%s\n", explain_connect(fildes, serv_addr,
		      serv_addr_size));
		  exit(EXIT_FAILURE);
	      }

       fildes  The original fildes, exactly as passed to the connect(2)	system
	       call.

       serv_addr
	       The original serv_addr, exactly as  passed  to  the  connect(2)
	       system call.

       serv_addr_size
	       The  original  serv_addr_size,  exactly	as  passed to the con-
	       nect(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, in-
	       cluding other threads.

       Note: This function is not thread safe, because it shares a return buf-
       fer across all threads, and many	other functions	in this	library.

   explain_errno_connect
       const  char *explain_errno_connect(int errnum, int fildes, const	struct
       sockaddr	*serv_addr, int	serv_addr_size);

       The explain_errno_connect function is used to obtain an explanation  of
       an error	returned by the	connect(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 fol-
       lowing example:
	      if (connect(fildes, serv_addr, serv_addr_size) < 0)
	      {
		  int err = errno;
		  fprintf(stderr, "%s\n", explain_errno_connect(err,
		      fildes, serv_addr, serv_addr_size));
		  exit(EXIT_FAILURE);
	      }

       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 connect(2)	system
	       call.

       serv_addr
	       The  original  serv_addr,  exactly  as passed to	the connect(2)
	       system call.

       serv_addr_size
	       The original serv_addr_size, exactly  as	 passed	 to  the  con-
	       nect(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,  in-
	       cluding other threads.

       Note: This function is not thread safe, because it shares a return buf-
       fer across all threads, and many	other functions	in this	library.

   explain_message_connect
       void  explain_message_connect(char  *message,  int  message_size,   int
       fildes, const struct sockaddr *serv_addr, int serv_addr_size);

       The explain_message_connect function may	be used	to  obtain an explana-
       tion of an error	returned by the	connect(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 fol-
       lowing example:
	      if (connect(fildes, serv_addr, serv_addr_size) < 0)
	      {
		  char message[3000];
		  explain_message_connect(message, sizeof(message),
		      fildes, serv_addr, serv_addr_size);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       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  re-
	       turned message.

       fildes  The original fildes, exactly as passed to the connect(2)	system
	       call.

       serv_addr
	       The original serv_addr, exactly as  passed  to  the  connect(2)
	       system call.

       serv_addr_size
	       The  original  serv_addr_size,  exactly	as  passed to the con-
	       nect(2) system call.

   explain_message_errno_connect
       void explain_message_errno_connect(char *message, int message_size, int
       errnum,	 int   fildes,	 const	 struct	  sockaddr   *serv_addr,   int
       serv_addr_size);

       The explain_message_errno_connect function may be used to obtain	an ex-
       planation  of  an  error	 returned  by the connect(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  fol-
       lowing example:
	      if (connect(fildes, serv_addr, serv_addr_size) < 0)
	      {
		  int err = errno;
		  char message[3000];
		  explain_message_errno_connect(message, sizeof(message), err,
		      fildes, serv_addr, serv_addr_size);
		  fprintf(stderr, "%s\n", message);
		  exit(EXIT_FAILURE);
	      }

       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 re-
	       turned 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 connect(2)	system
	       call.

       serv_addr
	       The  original  serv_addr,  exactly  as passed to	the connect(2)
	       system call.

       serv_addr_size
	       The original serv_addr_size, exactly  as	 passed	 to  the  con-
	       nect(2) system call.

SEE ALSO
       connect(2)
	       initiate	a connection on	a socket

       explain_connect_or_die(3)
	       initiate	a connection on	a socket and report errors

COPYRIGHT
       libexplain version 1.3
       Copyright (C) 2008 Peter	Miller

							    explain_connect(3)

NAME | SYNOPSIS | DESCRIPTION | SEE ALSO | COPYRIGHT

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