--- /dev/null
+/* cbake.l @BAKE flex @FILE && cc -std=c99 -D_GNU_SOURCE -o @SHORT lex.yy.c @ARGS -lfl @STOP */
+%{
+
+#include <ctype.h>
+
+#define backspace(fs) fputs("\x08", fs)
+#undef ECHO
+#define ECHO do { fprintf(stdout, yytext); if (gpipe) { fprintf(gpipe, yytext); } } while (0)
+#define CHAR(c) do { fputc(c, stdout); if (gpipe) { fputc(c, gpipe); } } while (0)
+#define STRING(s) do { fputs(s, stdout); if (gpipe) { fputs(s, gpipe); } } while (0)
+#define FORMAT(...) do { fprintf(stdout, __VA_ARGS__); if (gpipe) { fprintf(gpipe, __VA_ARGS__); } } while (0)
+#define FWRITE(str, len) do { fwrite(str, 1, len, stdout); if (gpipe) { fwrite(str, 1, len, gpipe); } } while (0)
+
+FILE * gpipe;
+
+char * filename;
+int gac;
+char ** gav;
+/* Options */
+int gselect = 1;
+/* Line accum */
+int line = 1;
+
+extern void root(char * filename);
+extern void args(int n);
+extern void shorten(char * filename, int n);
+%}
+
+SPACE [[:space:]]
+NUM [[:digit:]]
+
+%x FOUND
+
+%option nodefault
+%%
+<FOUND>{
+ \\. { /* skip next char */ ; }
+ @FILENAME|@FILE|$@ { STRING(filename); }
+ @SHORT:{NUM}+ { shorten(filename, atoi(strrchr(yytext, ':')+1)); }
+ @SHORT|$\* { shorten(filename, 1); }
+ @ARGS:{NUM}+ { args(atoi(strrchr(yytext, ':')+1)); }
+ @ARGS|$\+ { args(-1); }
+ @STOP { CHAR('\n'); if (gpipe) { fprintf(stderr, "output: "); } if (!gselect) { return 0; } BEGIN INITIAL; }
+ {SPACE}+ { CHAR(' '); }
+ . { ECHO; }
+}
+
+@BAKE{SPACE} { if (gselect < 0) { static int nth = 0; printf("%s:%d:s%d: ", filename, line, ++nth); BEGIN FOUND; } if (!--gselect) { BEGIN FOUND; } }
+\n|<FOUND>\n { ++line; }
+. { ; }
+%%
+
+void root(char * filename) {
+ char * path, * terminator;
+ if (!(path = realpath(filename, NULL))) { return; }
+ if (terminator = strrchr(path, '/')) {
+ *terminator = '\0';
+ chroot(path);
+ }
+ free(path);
+}
+
+void args(int n) {
+ if (n < 0) { for (int i = 0; i < gac; ++i) { STRING(gav[i]); if (i + 1 < gac) { CHAR(' '); } } }
+ else if (n < gac) { STRING(gav[n]); }
+}
+
+void shorten(char * filename, int n) {
+ char * end = filename + strlen(filename);
+ while (n && (end = memrchr(filename, '.', end - filename))) { --n; }
+ if (!end) { fprintf(stderr, "<SHORTEN> context error: Argument out of range.\n"); STRING("idiot"); return; }
+ FWRITE(filename, end - filename);
+}
+
+#define HELP \
+ "bake(1) - \"Buy high. Sell low.\"\n"
+void help(void) { puts(HELP); }
+
+int main (int ac, char ** av) {
+ int run = 1;
+ char * av0 = av[0];
+ FILE * fp, * op;
+
+ while (++av, --ac) {
+ int i;
+ if (av[0][0] != '-') { goto start; }
+ if (av[0][1] == '-') {
+ if (av[0][2] == '\0') { ++av, --ac; goto start; }
+ if (!strcmp(av[0]+2, "dry-run")) { i = strlen(av[0]); goto opt_dry_run; }
+ if (!strcmp(av[0]+2, "select" )) { if (!ac-1 || isdigit(av[1][0])) { goto opt_arg; } ++av, --ac;
+ i = strlen(av[0]); goto opt_select; }
+ if (!strcmp(av[0]+2, "list" )) { i = strlen(av[0]); goto opt_list; }
+ if (!strcmp(av[0]+2, "help" )) { goto opt_help; }
+ goto opt_default;
+ }
+ for (i = 1; i < strlen(av[0]); ++i) {
+ switch (av[0][i]) {
+ opt_dry_run: case 'n': run = 0; break;
+ opt_select: case 's': gselect = atoi(av[0]+2+(av[0][2] == '=')); break;
+ opt_list: case 'l': run = 0; gselect = -1; break;
+ opt_help: case 'h': help(); return 0;
+ opt_default: default: fprintf(stderr, "%s: Unknown option '%s'\n", av0, av[0]); return 1;
+ opt_arg: fprintf(stderr, "%s: Argument missing for '%s'\n", av0, av[0]); return 1;
+ }
+ }
+ }
+
+ start:
+ if (!ac) { fprintf(stderr, "%s: Missing filename\n", av0); return 1; }
+
+ /* filename and self placement */
+ filename = av[0];
+ root(filename);
+ {
+ char * tmp = strrchr(filename, '/');
+ if (tmp) { filename = tmp+1; }
+ }
+
+ /* open and prepare ac, av */
+ if (!(yyin = fp = fopen(filename, "rb")))
+ { fprintf(stderr, "%s: '%s' %s\n", av0, filename, strerror(errno)); return 1; }
+ gac = --ac, gav = ++av;
+
+ if (run) {
+ gpipe = popen("/bin/sh -e", "w");
+ if (!gpipe) { fprintf(stderr, "%s: <gpipe> %s\n", av0, strerror(errno)); return 1; }
+ }
+ if (gselect > 0) { fprintf(stderr, "%s: ", av0); fflush(stderr); }
+ yylex();
+ if (gselect > 0) { fprintf(stderr, "%s: Out of range\n", av0); }
+ fclose(fp);
+
+ if (run) { run = pclose(gpipe); if (run) { printf("%s: Exit code %d\n", av0, run); } return run; }
+ return 0;
+}