man ERR_error_string () - obtain human-readable error message
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); void 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
ERR_error_string() generates a human-readable string representing the error code e, and places it at buf. buf must be at least 120 bytes long. If buf is NULL, the error string is placed in a static buffer. ERR_error_string_n() is a variant of ERR_error_string() that writes at most len characters (including the terminating 0) and truncates the string if necessary. For ERR_error_string_n(), buf may not be NULL.
The string will have the following format:
error:[error code]:[library name]:[function name]:[reason string]
error code is an 8 digit hexadecimal number, library name, function name and reason string are ASCII text.
ERR_lib_error_string(), ERR_func_error_string() and ERR_reason_error_string() return the library name, function name and reason string respectively.
The OpenSSL error strings should be loaded by calling ERR_load_crypto_strings(3) or, for SSL applications, SSL_load_error_strings(3) first. If there is no text string registered for the given error code, the error string will contain the numeric code.
ERR_print_errors(3) can be used to print all error codes currently in the queue.
RETURN VALUES
ERR_error_string() returns a pointer to a static buffer containing the string if buf == NULL, buf otherwise.
ERR_lib_error_string(), ERR_func_error_string() and ERR_reason_error_string() return the strings, and NULL if none is registered for the error code.
SEE ALSO
HISTORY
ERR_error_string() is available in all versions of SSLeay and OpenSSL. ERR_error_string_n() was added in OpenSSL 0.9.6.