NAME
autoopt_parse_buffer_dest - parse destination for an output buffer
SYNOPSIS
#include <limb/autoopt.h>
int autoopt_parse_buffer_dest(const struct option *option, const char *arg, u8 *lvl)
DESCRIPTION
The autoopt_parse_buffer_dest() function parses arg to be the destination
for an output buffer. That is, it is expected to be either a file descriptor or
the name of a file that will be opened in append mode, parsed according to
open_parsed_name(3).
Additionally, it may be prefixed with an at-sign (@) followed by an output
level (as described in obuffer_parse_level(3)) and a colon (:), in order to
set the output level to specified level.
It is also possible not to specify a level (i.e. use @: as prefix) in order to
have the default level bumped (e.g. from OLVL_NORMAL to OLVL_VERBOSE).
To specify a file whose name begins with an at-sign, simply use two at-signs at the beginning of the file.
The option argument is only used in case of an error, to include the option's
name in the emitted warning.
The lvl argument is expected to point to the default level of the output
buffer, and might be changed according to the parsed arg, or set to -1 in case
of error.
RETURN VALUE
The function return the file descriptor to be used for the output buffer on
success. It can either be the specified file descriptor on arg, or - in case
of a file name - the file descriptor of the file opened in append mode.
Otherwise, it returns -1 and sets errno to indicate the error.
A warning it also emitted (through the warn(3) family of functions) describing the error.
ERRORS
The function may fail if :
EINVAL
Invalid output level specified, in which case the value pointed by lvl is
set to -1
It may also fail for the errors described for open_parsed_name(3) and open_append(3).