openssl/doc/crypto/ERR_error_string.pod
Rich Salz 9b86974e0c Fix L<> content in manpages
L<foo|foo> is sub-optimal  If the xref is the same as the title,
which is what we do, then you only need L<foo>.  This fixes all
1457 occurrences in 349 files.  Approximately.  (And pod used to
need both.)

Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-08-21 15:11:50 -04:00

73 lines
2.2 KiB
Text

=pod
=head1 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
=head1 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);
=head1 DESCRIPTION
ERR_error_string() generates a human-readable string representing the
error code I<e>, and places it at I<buf>. I<buf> must be at least 120
bytes long. If I<buf> is B<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 I<len> characters (including the terminating 0)
and truncates the string if necessary.
For ERR_error_string_n(), I<buf> may not be B<NULL>.
The string will have the following format:
error:[error code]:[library name]:[function name]:[reason string]
I<error code> is an 8 digit hexadecimal number, I<library name>,
I<function name> and I<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
L<ERR_load_crypto_strings(3)> or, for SSL
applications, L<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.
L<ERR_print_errors(3)> can be used to print
all error codes currently in the queue.
=head1 RETURN VALUES
ERR_error_string() returns a pointer to a static buffer containing the
string if I<buf> B<== NULL>, I<buf> otherwise.
ERR_lib_error_string(), ERR_func_error_string() and
ERR_reason_error_string() return the strings, and B<NULL> if
none is registered for the error code.
=head1 SEE ALSO
L<err(3)>, L<ERR_get_error(3)>,
L<ERR_load_crypto_strings(3)>,
L<SSL_load_error_strings(3)>
L<ERR_print_errors(3)>
=head1 HISTORY
ERR_error_string() is available in all versions of SSLeay and OpenSSL.
ERR_error_string_n() was added in OpenSSL 0.9.6.
=cut