ref: 1018d7a7091fd5e0433f501a3474cdc3fec322cc
dir: /appl/cmd/tac.b/
implement Tac; include "sys.m"; sys: Sys; include "bufio.m"; bufio: Bufio; Iobuf: import bufio; include "draw.m"; Tac: module { init: fn(nil: ref Draw->Context, args: list of string); }; stdout: ref Sys->FD; init(nil: ref Draw->Context, args: list of string) { sys = load Sys Sys->PATH; bufio = load Bufio Bufio->PATH; stdout = sys->fildes(1); args = tl args; if(args == nil) args = "-" :: nil; for(; args != nil; args = tl args) { file := hd args; if(file != "-") { fd := sys->open(file, Sys->OREAD); if(fd == nil){ sys->fprint(sys->fildes(2), "tac: cannot open %s: %r\n", file); raise "fail:bad open"; } tac(fd, file); } else { tac(sys->fildes(0), "<stdin>"); } } } tac(fd: ref Sys->FD, file: string) { lines: list of string = nil; line: string; fio := bufio->fopen(fd, bufio->OREAD); if(fio == nil) { sys->fprint(sys->fildes(2), "tac: Couldn't create a bufio for %s: %r\n", file); raise "fail:bufio"; } while((line = fio.gets('\n')) != nil) lines = line :: lines; while(lines != nil) { buf := array of byte (hd lines); sys->write(stdout, buf, len buf); lines = tl lines; } }