diff options
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 91 |
1 files changed, 91 insertions, 0 deletions
@@ -58325,6 +58325,97 @@ an argument, in cases when the callback has updated the Lisp object corresponding to a union member, and that change needs to be propagated to the foreign caller. +.SS* FFI-type-driven I/O Functions + +These functions provide a way to perform I/O on stream using the foreign +representation of Lisp objects, performing conversion between the Lisp +representations in memory and the foreign representations in a stream. + +The +.meta stream +argument used with these functions must be a stream object which, +in the case of input functions, supports +.code get-byte +and, in the case of output, supports +.codn put-byte . + +.coNP Function @ put-obj +.synb +.mets (put-obj < object < type <> [ stream ]) +.syne +.desc +The +.code put-obj +function encodes +.meta object +into a foreign representation, according to the FFI type +.metn type . +The bytes of the foreign representation are then written to +.metn stream . + +If +.meta stream +is omitted, it defaults to +.codn *stdout* . + +If the operation successfully writes all bytes of the representation to +.metn stream , +the value +.code t +is returned. A partial write causes the return value to be +.codn nil . + +All other stream error situations throw exceptions. + +.coNP Function @ get-obj +.synb +.mets (get-obj < type <> [ stream ]) +.syne +.desc +The +.code get-obj +function reads from +.meta stream +the bytes corresponding to a foreign representation according to the FFI type +.metn type . + +If +.meta stream +is omitted, it defaults to +.codn *stdin* . + +If the read is successful, these bytes are decoded, producing a Lisp +object, which is returned. + +If the read is incomplete, the value returned is +.metn nil . + +All other stream error situations throw exceptions. + +.coNP Function @ fill-obj +.synb +.mets (fill-obj < object < type <> [ stream ]) +.syne +.desc +The +.code get-obj +function reads from +.meta stream +the bytes corresponding to a foreign representation according to the FFI type +.metn type . + +If the read is successful, then +.meta object +is updated, if possible, from that representation, using the by-value in +semantics of the FFI type and returned. If a by-value update of +.meta object +isn't possible, then a new object is decoded from the data and returned. + +If the read is incomplete, the value returned is +.metn nil . + +All other stream error situations throw exceptions. + .SS* Buffer Functions Functions in this area provide a way to perform conversion between |