uri_scheme — copy a URI's scheme into a buffer
URI parsing library (liburi, -luri)
#include <liburi.h>
size_t uri_scheme(
URI *restrict uri,
char * buffer,
size_t size);
The uri_scheme function copies the scheme from a URI
into a supplied buffer.
uriThe source URI to copy the scheme from.
buffer
The buffer to store the URI's scheme in. buffer
may be NULL to simply obtain the return
value.
The string stored in buffer will always be
NULL-terminated, even if the buffer is not
large enough to hold the entire string, provided
buffer is not-NULL and
size is non-zero.
size
The size of buffer, in bytes.
If successful, uri_scheme returns the total number
of bytes required to store the URI's scheme, including the
NULL terminator (that is, one greater than
the length of the string measured in bytes). This return will
occur whether a buffer is supplied or not, and regardless of its size.
If the URI has no scheme, uri_scheme will return
0, however it will still copy an empty string to
buffer provided buffer
is non-NULL and size
is non-zero.
If an error occurs, uri_scheme returns
(size_t) -1, and sets errno
accordingly.
An application can invoke uri_scheme, passing
NULL as buffer and
0 as size in order to
obtain the size of buffer required for a subsequent call.
Alternatively, if buffer was
non-NULL, an application can compare
the return value with the supplied size
in order to to determine whether the copied string was truncated: if
the return value is less than or equal to size,
truncation did not occur.
#define BUFFER_SIZE 8
URI *uri;
char buffer[BUFFER_SIZE];
size_t r;
uri = uri_create_str("http://example.com/", NULL);
r = uri_scheme(uri, buffer, BUFFER_SIZE);
/* assuming no errors have occurred, buffer will contain 'http' and
* r will be 5.
*/
printf("buffer='%s', r=%lu\n", buffer, (unsigned long) r);
liburi(3).