listamsb: reword some warnings.

1 files changed, 17 insertions, 4 deletions

diff --git a/listamsb.c b/listamsb.c
index f11110a..6d125b9 100644
--- a/listamsb.c
+++ b/listamsb.c
@@ -99,7 +99,7 @@ int read_header(void) {
 	}
 
 	if(proglen < MIN_PROGLEN) {
-		fprintf(stderr, "%s: not an AMSB file: program size in header too small (%d)\n",
+		fprintf(stderr, "%s: not an AMSB file: program size too small (%d). Atari BASIC file?\n",
 				self, proglen);
 		exit(1);
 	}
@@ -195,6 +195,12 @@ int next_line(void) {
 			unknown_token(lineno, byte, 0);
 		} else {
 			if(!byte) break;
+			if(byte < 0x20) {
+				/* ATASCII graphics outside of a string */
+				fprintf(stderr, "%s: line %d has character %d outside of a string, "
+						"maybe not an AMSB file?\n",
+						self, lineno, byte);
+			}
 			putc(byte, outfile);
 		}
 	}
@@ -267,10 +273,14 @@ void open_output() {
 			perror("/dev/null");
 			exit(1);
 		}
+		if(verbose)
+			fprintf(stderr, "using /dev/null for output (check_only)\n");
 	} else if(raw_output) {
 		if(isatty(fileno(stdout)))
 			die("refusing to write raw ATASCII to a terminal");
 		outfile = stdout;
+		if(verbose)
+			fprintf(stderr, "using stdout for output\n");
 	} else {
 		if(verbose)
 			fprintf(stderr, "using pipe for output: %s\n", pipe_command);
@@ -304,7 +314,7 @@ int main(int argc, char **argv) {
 		if(verbose)
 			fprintf(stderr, "file size matches proglen\n");
 	} else {
-		fprintf(stderr, "%s: file size doesn't match length in header\n", self);
+		fprintf(stderr, "%s: actual program size doesn't match program size in header\n", self);
 	}
 
 	if(fgetc(infile) != EOF) {
@@ -312,12 +322,15 @@ int main(int argc, char **argv) {
 	}
 
 	if(unknowns) {
-		fprintf(stderr, "%s: input has %d unknown tokens\n", self, unknowns);;
+		fprintf(stderr, "%s: file has %d unknown tokens\n", self, unknowns);;
 		rv = 2;
 	}
 
 	if(need_pclose) {
-		if(pclose(outfile) != 0) {
+		int got = pclose(outfile);
+		if(verbose)
+			fprintf(stderr, "return value from pipe is %d\n", got);
+		if(got != 0) {
 			die("a8cat child process failed, do you have a8cat on your PATH?");
 		}
 	}