Skip site navigation (1)Skip section navigation (2)

  
 
  

home | help
explain_execlp(3)	    Library Functions Manual	       explain_execlp(3)

NAME
     explain_execlp - explain execlp(3) errors

SYNOPSIS
     #include <libexplain/execlp.h>
     const char *explain_execlp(, ...);
     const char *explain_errno_execlp(int errnum, , ...);
     void explain_message_execlp(char *message, int message_size, , ...);
     void explain_message_errno_execlp(char *message, int message_size, int er-
     rnum, , ...);

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

   explain_execlp
     const char *explain_execlp(, ...);

     The explain_execlp function is used to obtain an explanation  of  an  error
     returned  by  the execlp(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.

     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:
	    if (execlp() < 0)
	    {
		fprintf(stderr, "%s\n", explain_execlp());
		exit(EXIT_FAILURE);
	    }

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

   explain_errno_execlp
     const char *explain_errno_execlp(int errnum, , ...);

     The  explain_errno_execlp	function  is used to obtain an explanation of an
     error returned by the execlp(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.

     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:
	    if (execlp() < 0)
	    {
		int err = errno;
		fprintf(stderr, "%s\n", explain_errno_execlp(err, ));
		exit(EXIT_FAILURE);
	    }

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

   explain_message_execlp
     void explain_message_execlp(char *message, int message_size, , ...);

     The  explain_message_execlp function is used to obtain an explanation of an
     error returned by the execlp(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.

     Example:  This  function is intended to be used in a fashion similar to the
     following example:
	    if (execlp() < 0)
	    {
		char message[3000];
		explain_message_execlp(message, sizeof(message), );
		fprintf(stderr, "%s\n", message);
		exit(EXIT_FAILURE);
	    }

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

   explain_message_errno_execlp
     void explain_message_errno_execlp(char *message, int message_size, int er-
     rnum, , ...);

     The  explain_message_errno_execlp function is used to obtain an explanation
     of an error returned by the execlp(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.

     Example: This function is intended to be used in a fashion similar  to  the
     following example:
	    if (execlp() < 0)
	    {
		int err = errno;
		char message[3000];
		explain_message_errno_execlp(message, sizeof(message), err, );
		fprintf(stderr, "%s\n", message);
		exit(EXIT_FAILURE);
	    }

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

SEE ALSO
     execlp(3)
	     execute a file

     explain_execlp_or_die(3)
	     execute a file and report errors

COPYRIGHT
     libexplain version 1.3
     Copyright (C) 2009 Peter Miller

							       explain_execlp(3)

Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=explain_execlp&sektion=3&manpath=FreeBSD+Ports+15.1.quarterly>

home | help