ERR_error_string(3) — Subroutines

NAME

ERR_error_string, ERR_error_string_n, ERR_lib_error_string, ERR_func_error_string, ERR_reason_error_string − Obtain human-readable error message

SYNOPSIS

#include <openssl/err.h>
char ∗ERR_error_string(
        unsigned long e, char ∗buf ); char ∗ERR_error_string_n(
        unsigned long e, char ∗buf, size_t len ); const char ∗ERR_lib_error_string(
        unsigned long e ); const char ∗ERR_func_error_string(
        unsigned long e ); const char ∗ERR_reason_error_string(
        unsigned long e );

DESCRIPTION

The ERR_error_string() function generates a human-readable string representing the error code e, and places it at buf. The buf must be at least 120 bytes long. If buf is NULL, the error string is placed in a static buffer. The ERR_error_string_n() function is a variant of the ERR_error_string() functon that writes at most len characters (including the terminating 0) and truncates the string if necessary. For ERR_error_string_n(), buf cannot be NULL.

The string will have the following format:

error:[error code]:[library name]:[function name]:[reason string]

The error code is an 8−digit hexadecimal number. The library name, function name, and reason string are ASCII text.

The ERR_lib_error_string(), ERR_func_error_string(), and ERR_reason_error_string() functions return the library name, function name and reason string respectively.

The OpenSSL error strings should be loaded by first calling ERR_load_crypto_strings() or, for SSL applications, SSL_load_error_strings(). If there is no text string registered for the given error code, the error string will contain the numeric code.

The ERR_print_errors() function can be used to print all error codes currently in the queue.

RETURN VALUES

The ERR_error_string() function returns a pointer to a static buffer containing the string if buf == NULL, buf otherwise.

The ERR_lib_error_string(), ERR_func_error_string(), and ERR_reason_error_string() functions return the strings, and NULL if none is registered for the error code.

HISTORY

The ERR_error_string() function is available in all versions of SSLeay and OpenSSL. The ERR_error_string_n() function was added in OpenSSL 0.9.6.

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