libexplain
1.4.D001
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explain getchar(3) errors More...
#include <libexplain/gcc_attributes.h>
#include <libexplain/large_file_support.h>
#include <stdio.h>
Go to the source code of this file.
Functions | |
int | explain_getchar_or_die (void) |
int | explain_getchar_on_error (void) LIBEXPLAIN_WARN_UNUSED_RESULT |
const char * | explain_getchar (void) LIBEXPLAIN_WARN_UNUSED_RESULT |
const char * | explain_errno_getchar (int errnum) LIBEXPLAIN_WARN_UNUSED_RESULT |
void | explain_message_getchar (char *message, int message_size) |
void | explain_message_errno_getchar (char *message, int message_size, int errnum) |
explain getchar(3) errors
Definition in file getchar.h.
const char* explain_errno_getchar | ( | int | errnum | ) |
The explain_errno_getchar function is used to obtain an explanation of an error returned by the getchar(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.
This function is intended to be used in a fashion similar to the following example:
int c = getchar(); if (c == EOF && ferror(stdin)) { int err = errno; fprintf(stderr, "%s\n", explain_errno_getchar(err, )); exit(EXIT_FAILURE); }
The above code example is available pre-packaged as the explain_getchar_or_die function.
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. |
const char* explain_getchar | ( | void | ) |
The explain_getchar function is used to obtain an explanation of an error returned by the getchar(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.
This function is intended to be used in a fashion similar to the following example:
int c = getchar(); if (c == EOF && ferror(stdin)) { fprintf(stderr, "%s\n", explain_getchar()); exit(EXIT_FAILURE); }
The above code example is available pre-packaged as the explain_getchar_or_die function.
int explain_getchar_on_error | ( | void | ) |
The explain_getchar_on_error function is used to call the getchar(3) system call. On failure an explanation will be printed to stderr, obtained from the explain_getchar(3) function.
This function is intended to be used in a fashion similar to the following example:
int c = explain_getchar_on_error(); if (c == EOF && ferror(stdin)) { ...cope with error ...no need to print error message }
int explain_getchar_or_die | ( | void | ) |
The explain_getchar_or_die function is used to call the getchar(3) system call. On failure an explanation will be printed to stderr, obtained from the explain_getchar(3) function, and then the process terminates by calling exit(EXIT_FAILURE).
This function is intended to be used in a fashion similar to the following example:
int c = explain_getchar_or_die();
void explain_message_errno_getchar | ( | char * | message, |
int | message_size, | ||
int | errnum | ||
) |
The explain_message_errno_getchar function is used to obtain an explanation of an error returned by the getchar(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.
This function is intended to be used in a fashion similar to the following example:
int c = getchar(); if (c == EOF && ferror(stdin)) { int err = errno; char message[3000]; explain_message_errno_getchar(message, sizeof(message), err, ); fprintf(stderr, "%s\n", message); exit(EXIT_FAILURE); }
The above code example is available pre-packaged as the explain_getchar_or_die function.
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 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. |
void explain_message_getchar | ( | char * | message, |
int | message_size | ||
) |
The explain_message_getchar function is used to obtain an explanation of an error returned by the getchar(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.
This function is intended to be used in a fashion similar to the following example:
int c = getchar(); if (c == EOF && ferror(stdin)) { char message[3000]; explain_message_getchar(message, sizeof(message), ); fprintf(stderr, "%s\n", message); exit(EXIT_FAILURE); }
The above code example is available pre-packaged as the explain_getchar_or_die function.
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. |