forgot to add man page

buffer/bs_capacityassert.3

@@ -0,0 +1,31 @@
+.TH bs_capacityassert 3
+.SH NAME
+bs_capacityassert \- assert that there are least n bytes left in the stream
+.SH SYNTAX
+.B #include <libowfat/parse.h>
+
+int \fBbs_capacityassert\fR(struct bytestream* &\fIbs\fR,
+                size_t \fIcapacity\fR);
+.SH DESCRIPTION
+bs_capacityassert will check that there are at least this many bytes in
+the bytestream. If there are not, it will set the bytestream to the
+error state and return 0; otherwise it will return 1.
+
+Note that this compares against the limits of the bytestream, not the
+actual length. These are often the same, but bytestreams can be tied
+to a buffer*, in which case the actual length of the stream is not known
+beforehand. Even if bs_capacityassert returns successful, the following
+actual reads could still run into an error.
+
+bs_capacitycheck does the same thing but does not set the bytestream to
+the error state if there is not enough space.
+
+Us bs_capacityleft to find out how many bytes are left in the bytestream.
+
+bs_nomoredataassert is the inverse assertion.
+
+Use bs_err to find out whether the bytestream is in the error state.
+.SH "SEE ALSO"
+bs_init_membuf(3), bs_init_iobuf(3), bs_init_iobuf_size(3),
+bs_init_membuf(3), bs_capacitycheck(3), bs_capacityleft(3),
+bs_err(3), bs_nomoredataassert(3)