libexplain  1.4.D001
Functions
libexplain/sprintf.c File Reference
#include <libexplain/ac/errno.h>
#include <libexplain/ac/stdio.h>
#include <libexplain/buffer/errno/sprintf.h>
#include <libexplain/common_message_buffer.h>
#include <libexplain/sprintf.h>

Go to the source code of this file.

Functions

const char * explain_sprintf (char *data, const char *format,...)
const char * explain_errno_sprintf (int errnum, char *data, const char *format,...)
void explain_message_sprintf (char *message, int message_size, char *data, const char *format,...)
void explain_message_errno_sprintf (char *message, int message_size, int errnum, char *data, const char *format,...)

Function Documentation

const char* explain_errno_sprintf ( int  errnum,
char *  data,
const char *  format,
  ... 
)

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

Parameters:
errnumThe 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.
dataThe original data, exactly as passed to the sprintf(3) system call.
formatThe original format, exactly as passed to the sprintf(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 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.
Example:
This function is intended to be used in a fashion similar to the following example:
 errno = EINVAL;
 int result = sprintf(data, format, ...);
 if (result < 0)
 {
     int err = errno;
     fprintf(stderr, "%s\n", explain_errno_sprintf(err, data, format, ...));
     exit(EXIT_FAILURE);
 }
The above code example is available pre-packaged as the explain_sprintf_or_die function.

Definition at line 49 of file sprintf.c.

void explain_message_errno_sprintf ( char *  message,
int  message_size,
int  errnum,
char *  data,
const char *  format,
  ... 
)

Definition at line 84 of file sprintf.c.

void explain_message_sprintf ( char *  message,
int  message_size,
char *  data,
const char *  format,
  ... 
)

Definition at line 68 of file sprintf.c.

const char* explain_sprintf ( char *  data,
const char *  format,
  ... 
)

The explain_sprintf function is used to obtain an explanation of an error returned by the sprintf(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 decoded.

Parameters:
dataThe original data, exactly as passed to the sprintf(3) system call.
formatThe original format, exactly as passed to the sprintf(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 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.
Example:
This function is intended to be used in a fashion similar to the following example:
 errno = EINVAL;
 int result = sprintf(data, format, ...);
 if (result < 0)
 {
     fprintf(stderr, "%s\n", explain_sprintf(data, format, ...));
     exit(EXIT_FAILURE);
 }
The above code example is available pre-packaged as the explain_sprintf_or_die function.

Definition at line 28 of file sprintf.c.