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explain_tmpnam(3)	    Library Functions Manual	       explain_tmpnam(3)

NAME
     explain_tmpnam - explain tmpnam(3) errors

SYNOPSIS
     #include <libexplain/tmpnam.h>
     const char *explain_tmpnam(char *pathname);
     const char *explain_errno_tmpnam(int errnum, char *pathname);
     void explain_message_tmpnam(char *message, int message_size, char *path-
     name);
     void explain_message_errno_tmpnam(char *message, int message_size, int er-
     rnum, char *pathname);

DESCRIPTION
     These  functions  may be used to obtain explanations for errors returned by
     the tmpnam(3) system call.

   explain_tmpnam
     const char *explain_tmpnam(char *pathname);

     The explain_tmpnam function is used to obtain an explanation  of  an  error
     returned  by  the tmpnam(3) 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 de-
     coded.

     pathname
	     The original pathname, exactly as passed to  the  tmpnam(3)  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  ar-
	     gument list.  This will be overwritten by the next call to any lib-
	     explain 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.

     Example: This function is intended to be used in a fashion similar  to  the
     following example:
	    char *result = tmpnam(pathname);
	    if (!result)
	    {
		fprintf(stderr, "%s\n", explain_tmpnam(pathname));
		exit(EXIT_FAILURE);
	    }

     The  above  code  example	is  available  pre-packaged  as the explain_tmp-
     nam_or_die(3) function.

   explain_errno_tmpnam
     const char *explain_errno_tmpnam(int errnum, char *pathname);

     The explain_errno_tmpnam function is used to obtain an  explanation  of  an
     error  returned  by  the  tmpnam(3) system call. The least the message will
     contain is the value of strerror(errno), but usually it will do  much  bet-
     ter, and indicate the underlying cause in more detail.

     errnum  The  error  value	to  be	decoded, usually obtained from the errno
	     global variable just before this function is called. This is neces-
	     sary if you need to call any code between the system call to be ex-
	     plained and this function, because many libc functions  will  alter
	     the value of errno.

     pathname
	     The  original  pathname,  exactly as passed to the tmpnam(3) 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 ar-
	     gument list.  This will be overwritten by the next call to any lib-
	     explain 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.

     Example:  This  function is intended to be used in a fashion similar to the
     following example:
	    char *result = tmpnam(pathname);
	    if (!result)
	    {
		int err = errno;
		fprintf(stderr, "%s\n", explain_errno_tmpnam(err, pathname));
		exit(EXIT_FAILURE);
	    }

     The above code  example  is  available  pre-packaged  as  the  explain_tmp-
     nam_or_die(3) function.

   explain_message_tmpnam
     void explain_message_tmpnam(char *message, int message_size, char *path-
     name);

     The  explain_message_tmpnam function is used to obtain an explanation of an
     error returned by the tmpnam(3) system call. The  least  the  message  will
     contain  is  the value of strerror(errno), but usually it will do much bet-
     ter, and indicate the underlying cause in more detail.

     The errno global variable will be used to obtain the error value to be  de-
     coded.

     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.

     pathname
	     The  original  pathname,  exactly as passed to the tmpnam(3) system
	     call.

     Example: This function is intended to be used in a fashion similar  to  the
     following example:
	    char *result = tmpnam(pathname);
	    if (!result)
	    {
		char message[3000];
		explain_message_tmpnam(message, sizeof(message), pathname);
		fprintf(stderr, "%s\n", message);
		exit(EXIT_FAILURE);
	    }

     The  above  code  example	is  available  pre-packaged  as the explain_tmp-
     nam_or_die(3) function.

   explain_message_errno_tmpnam
     void explain_message_errno_tmpnam(char *message, int message_size, int er-
     rnum, char *pathname);

     The explain_message_errno_tmpnam function is used to obtain an  explanation
     of  an  error  returned by the tmpnam(3) 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.

     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 neces-
	     sary if you need to call any code between the system call to be ex-
	     plained and this function, because many libc functions  will  alter
	     the value of errno.

     pathname
	     The  original  pathname,  exactly as passed to the tmpnam(3) system
	     call.

     Example: This function is intended to be used in a fashion similar  to  the
     following example:
	    char *result = tmpnam(pathname);
	    if (!result)
	    {
		int err = errno;
		char message[3000];
		explain_message_errno_tmpnam(message, sizeof(message), err,
		pathname);
		fprintf(stderr, "%s\n", message);
		exit(EXIT_FAILURE);
	    }

     The  above  code  example	is  available  pre-packaged  as the explain_tmp-
     nam_or_die(3) function.

SEE ALSO
     tmpnam(3)
	     create a name for a temporary file

     explain_tmpnam_or_die(3)
	     create a name for a temporary file and report errors

COPYRIGHT
     libexplain version 1.3
     Copyright (C) 2010 Peter Miller

							       explain_tmpnam(3)

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