libs/libc/stdio/Kconfig

#
# For a description of the syntax of this configuration file,
# see the file kconfig-language.txt in the NuttX tools repository.
#

menu "Standard C I/O"

config STDIO_DISABLE_BUFFERING
	bool "Disable STDIO Buffering"
	depends on FILE_STREAM
	default n
	---help---
		Tiny systems may need to disable all support for I/O buffering in
		order to minimize the memory footprint.

		NOTE that even if STDIO buffering is enabled, you can still disable
		buffering by setting CONFIG_STDIO_BUFFER_SIZE=0 or dynamically
		through the setvbuf() interface.  In this case, however,  memory
		used for buffering will be eliminated, of course, but there will be
		no reduction in static code size.  Only setting
		CONFIG_STDIO_DISABLE_BUFFERING will reduce static code size.

		The setvbuf() interface is not available if
		CONFIG_STDIO_DISABLE_BUFFERING is selected.

if !STDIO_DISABLE_BUFFERING

config STDIO_BUFFER_SIZE
	int "STDIO buffer size"
	default 64
	---help---
		Size of buffers using within the C buffered I/O interfaces (printf,
		putchar, fwrite, etc.).  This function sets the initial I/O buffer
		size.  Zero disables I/O buffering initially.  Any buffer size may
		be subsequently modified using setvbuf().

config STDIO_LINEBUFFER
	bool "STDIO line buffering"
	default y
	---help---
		Sets the default behavior to flush buffered I/O whenever a newline
		character is found in the output data stream.  This setting just
		sets the initial default behavior of all streams.  The behavior of
		an individual stream can be changed via setvbuf().

endif # !STDIO_DISABLE_BUFFERING

config NUNGET_CHARS
	int "Number unget() characters"
	default 2
	---help---
		Number of characters that can be buffered by ungetc() (Only if
		FILE_STREAM equals y)

config LIBC_FLOATINGPOINT
	bool "Enable floating point in printf"
	default !DEFAULT_SMALL && ARCH_FPU
	depends on !LIBM_NONE
	---help---
		By default, floating point support in printf, sscanf, etc. is
		disabled.  This option will enable floating point support.

config LIBC_LONG_LONG
	bool "Enable long long support in printf"
	default !DEFAULT_SMALL
	---help---
		Enables support for long long formats in printf, sscanf, etc. is
		enabled.  This is enabled by default but if you are trying to
		reduce the FLASH footprint, then disabling this feature is one
		option.  The FLASH saves comes not from disabling the long long
		formats, but rather from omitting the large long long arithmetic
		libraries that will be drawn into the build if long long support
		is enabled.

		NOTE:  This setting has no effect if the underlying architecture
		cannot support long long types

config LIBC_NUMBERED_ARGS
	bool "Enable numbered arguments in printf"
	default n
	---help---
		Enables support for numbered arguments in printf.

		  printf("%3$s %3$s %1$s %2$s\n", "1", "2", "3"); --> "3 3 1 2"
		  printf("%3$*2$.*1$f\n", 4, 8, 1.234567); --> "  1.2346"

		Attention: Mixing of numbered and sequential arguments in one
		format string is not allowed according to POSIX.

config LIBC_NL_ARGMAX
	int "Maximum number of numbered arguments for printf"
	default 9
	range 9 999999
	depends on LIBC_NUMBERED_ARGS
	---help---
		Applies only if there are numbered arguments in your format string.
		The number of sequential arguments isn't affected.
		Will be copied into stdio POSIX macro NL_ARGMAX.

		Attention: Increasing this value will increase stack usage
		of printf.

config LIBC_SCANSET
	bool "Scanset support"
	default n
	---help---
		Add scanset support to sscanf().

config LIBC_PRINT_EXTENSION
	bool
	default n
	---help---
		Enables non-standard "%p*" extensions for the printf family.

		CAVEAT: If your system is using any of the printf C family
		functions, it's probably unsafe to enable this option because
		the extension is not compatible with the C standard. Namely,
		an ordinary character following a "%p" conversion is interpreted
		in a non-standard way, which might crash the code which expects
		the standard semantics. For that reason, in the future versions
		of NuttX, this extension might be removed, or changed in an
		API-incompatible way to avoid conflicts with the standards.
		(Eg. use different characters for conversions specifiers,
		or switch to a completely separate API, say "nuttx_printf".)

endmenu #Standard C I/O