linux man page for err_peek_error_line_data

ERR_get_error(3SSL)						      OpenSSL						       ERR_get_error(3SSL)

NAME
       ERR_get_error, ERR_peek_error, ERR_peek_last_error, ERR_get_error_line, ERR_peek_error_line, ERR_peek_last_error_line,
       ERR_get_error_line_data, ERR_peek_error_line_data, ERR_peek_last_error_line_data - obtain error code and data

SYNOPSIS
	#include <openssl/err.h>

	unsigned long ERR_get_error(void);
	unsigned long ERR_peek_error(void);
	unsigned long ERR_peek_last_error(void);

	unsigned long ERR_get_error_line(const char **file, int *line);
	unsigned long ERR_peek_error_line(const char **file, int *line);
	unsigned long ERR_peek_last_error_line(const char **file, int *line);

	unsigned long ERR_get_error_line_data(const char **file, int *line,
		const char **data, int *flags);
	unsigned long ERR_peek_error_line_data(const char **file, int *line,
		const char **data, int *flags);
	unsigned long ERR_peek_last_error_line_data(const char **file, int *line,
		const char **data, int *flags);

DESCRIPTION
       ERR_get_error() returns the earliest error code from the thread's error queue and removes the entry. This function can be called repeatedly
       until there are no more error codes to return.

       ERR_peek_error() returns the earliest error code from the thread's error queue without modifying it.

       ERR_peek_last_error() returns the latest error code from the thread's error queue without modifying it.

       See ERR_GET_LIB(3) for obtaining information about location and reason of the error, and ERR_error_string(3) for human-readable error
       messages.

       ERR_get_error_line(), ERR_peek_error_line() and ERR_peek_last_error_line() are the same as the above, but they additionally store the file
       name and line number where the error occurred in *file and *line, unless these are NULL.

       ERR_get_error_line_data(), ERR_peek_error_line_data() and ERR_get_last_error_line_data() store additional data and flags associated with
       the error code in *data and *flags, unless these are NULL. *data contains a string if *flags&ERR_TXT_STRING. If it has been allocated by
       OPENSSL_malloc(), *flags&ERR_TXT_MALLOCED is true.

RETURN VALUES
       The error code, or 0 if there is no error in the queue.

SEE ALSO
       err(3), ERR_error_string(3), ERR_GET_LIB(3)

HISTORY
       ERR_get_error(), ERR_peek_error(), ERR_get_error_line() and ERR_peek_error_line() are available in all versions of SSLeay and OpenSSL.
       ERR_get_error_line_data() and ERR_peek_error_line_data() were added in SSLeay 0.9.0.  ERR_peek_last_error(), ERR_peek_last_error_line() and
       ERR_peek_last_error_line_data() were added in OpenSSL 0.9.7.

1.0.0e								    2002-11-29						       ERR_get_error(3SSL)