Function

VipsForeignmap

Declaration [src]

void*
vips_foreign_map (
  const char* base,
  VipsSListMap2Fn fn,
  void* a,
  void* b
)

Description [src]

Apply a function to every VipsForeign that VIPS knows about. Foreigns are presented to the function in priority order.

Like all VIPS map functions, if fn returns NULL, iteration continues. If it returns non-NULL, iteration terminates and that value is returned. The map function returns NULL if all calls return NULL.

::: seealso vips_slist_map2().

Parameters

`base`	`const char*`
	Base class to search below (eg. “VipsForeignLoad”)
	The data is owned by the caller of the function.
	The string is a NUL terminated UTF-8 string.
`fn`	`VipsSListMap2Fn`
	Function to apply to each `VipsForeign`
`a`	`void*`
	User data.
	The argument can be `NULL`.
	The data is owned by the caller of the function.
`b`	`void*`
	User data.
	The argument can be `NULL`.
	The data is owned by the caller of the function.

Return value

Returns:	`gpointer`
	The result of iteration.
	The data is owned by the called function.
	The return value can be `NULL`.