libexplain  1.4.D001
Functions
libexplain/ftime.h File Reference

explain ftime(3) errors More...

#include <libexplain/gcc_attributes.h>
#include <libexplain/large_file_support.h>
#include <time.h>
#include <sys/timeb.h>

Go to the source code of this file.

Functions

void explain_ftime_or_die (struct timeb *tp)
int explain_ftime_on_error (struct timeb *tp) LIBEXPLAIN_WARN_UNUSED_RESULT
const char * explain_ftime (struct timeb *tp) LIBEXPLAIN_WARN_UNUSED_RESULT
const char * explain_errno_ftime (int errnum, struct timeb *tp) LIBEXPLAIN_WARN_UNUSED_RESULT
void explain_message_ftime (char *message, int message_size, struct timeb *tp)
void explain_message_errno_ftime (char *message, int message_size, int errnum, struct timeb *tp)

Detailed Description

explain ftime(3) errors

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

Definition in file ftime.h.


Function Documentation

const char* explain_errno_ftime ( int  errnum,
struct timeb *  tp 
)

The explain_errno_ftime function is used to obtain an explanation of an error returned by the ftime(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.
tpThe original tp, exactly as passed to the ftime(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:
 if (ftime(tp) < 0)
 {
     int err = errno;
     fprintf(stderr, "%s\n", explain_errno_ftime(err, tp));
     exit(EXIT_FAILURE);
 }
The above code example is available pre-packaged as the explain_ftime_or_die function.
const char* explain_ftime ( struct timeb *  tp)

The explain_ftime function is used to obtain an explanation of an error returned by the ftime(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:
tpThe original tp, exactly as passed to the ftime(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:
 if (ftime(tp) < 0)
 {
     fprintf(stderr, "%s\n", explain_ftime(tp));
     exit(EXIT_FAILURE);
 }
The above code example is available pre-packaged as the explain_ftime_or_die function.
int explain_ftime_on_error ( struct timeb *  tp)

The explain_ftime_on_error function is used to call the ftime(3) system call. On failure an explanation will be printed to stderr, obtained from the explain_ftime(3) function.

Parameters:
tpThe tp, exactly as to be passed to the ftime(3) system call.
Returns:
The value returned by the wrapped ftime(3) system call.
Example:
This function is intended to be used in a fashion similar to the following example:
 if (explain_ftime_on_error(tp) < 0)
 {
     ...cope with error
     ...no need to print error message
 }
void explain_ftime_or_die ( struct timeb *  tp)

The explain_ftime_or_die function is used to call the ftime(3) system call. On failure an explanation will be printed to stderr, obtained from the explain_ftime(3) function, and then the process terminates by calling exit(EXIT_FAILURE).

Parameters:
tpThe tp, exactly as to be passed to the ftime(3) system call.
Returns:
This function only returns on success, see ftime(3) for more information. On failure, prints an explanation and exits, it does not return.
Example:
This function is intended to be used in a fashion similar to the following example:
void explain_message_errno_ftime ( char *  message,
int  message_size,
int  errnum,
struct timeb *  tp 
)

The explain_message_errno_ftime function is used to obtain an explanation of an error returned by the ftime(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:
messageThe location in which to store the returned message. If a suitable message return buffer is supplied, this function is thread safe.
message_sizeThe size in bytes of the location in which to store the returned message.
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.
tpThe original tp, exactly as passed to the ftime(3) system call.
Example:
This function is intended to be used in a fashion similar to the following example:
 if (ftime(tp) < 0)
 {
     int err = errno;
     char message[3000];
     explain_message_errno_ftime(message, sizeof(message), err, tp);
     fprintf(stderr, "%s\n", message);
     exit(EXIT_FAILURE);
 }
The above code example is available pre-packaged as the explain_ftime_or_die function.
void explain_message_ftime ( char *  message,
int  message_size,
struct timeb *  tp 
)

The explain_message_ftime function is used to obtain an explanation of an error returned by the ftime(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.

The errno global variable will be used to obtain the error value to be decoded.

Parameters:
messageThe location in which to store the returned message. If a suitable message return buffer is supplied, this function is thread safe.
message_sizeThe size in bytes of the location in which to store the returned message.
tpThe original tp, exactly as passed to the ftime(3) system call.
Example:
This function is intended to be used in a fashion similar to the following example:
 if (ftime(tp) < 0)
 {
     char message[3000];
     explain_message_ftime(message, sizeof(message), tp);
     fprintf(stderr, "%s\n", message);
     exit(EXIT_FAILURE);
 }
The above code example is available pre-packaged as the explain_ftime_or_die function.