listamsb: allow overriding a8cat path in environment.

3 files changed, 34 insertions, 1 deletions

diff --git a/listamsb.1 b/listamsb.1
index 1302ae6..f1b34e0 100644
--- a/listamsb.1
+++ b/listamsb.1
@@ -27,7 +27,7 @@ level margin: \\n[rst2man-indent\\n[rst2man-indent-level]]
 .\" new: \\n[rst2man-indent\\n[rst2man-indent-level]]
 .in \\n[rst2man-indent\\n[rst2man-indent-level]]u
 ..
-.TH "LISTAMSB" 1 "2025-03-07" "0.2.1" "Urchlay's Atari 8-bit Tools"
+.TH "LISTAMSB" 1 "2025-03-08" "0.2.1" "Urchlay's Atari 8-bit Tools"
 .SH NAME
 listamsb \- List the source of a tokenized Atari Microsoft BASIC program
 .SH SYNOPSIS
@@ -239,6 +239,17 @@ of Microsoft BASIC (e.g. Commodore, AppleSoft, GW\-BASIC, TRS\-80). If
 you see this warning, you\(aqll also see \fIN\fP <unknown token \fIXX\fP>
 messages in the actual listing.
 .UNINDENT
+.SH ENVIRONMENT
+.sp
+\fBA8CAT\fP
+.INDENT 0.0
+.INDENT 3.5
+The path to the \fBa8cat\fP(1) binary. Can be a full path or just
+the executable name, in which case it will be searched for with the
+normal \fBPATH\fP mechanism. If not set, \fIa8cat\fP is used. If there are
+spaces or other metacharacters, they must be escaped.
+.UNINDENT
+.UNINDENT
 .SH LIMITATIONS
 .sp
 Unlike \fBlistbas\fP, there\(aqs no color syntax highlighting. Probably there
diff --git a/listamsb.c b/listamsb.c
index 7195443..7d9ca81 100644
--- a/listamsb.c
+++ b/listamsb.c
@@ -751,9 +751,15 @@ void get_line_range(const char *arg) {
 }
 
 void parse_args(int argc, char **argv) {
+	const char *a8cat;
 	char tmp[10];
 	int opt;
 
+	a8cat = getenv("A8CAT");
+	if(!a8cat) a8cat = "a8cat";
+
+	strncpy(pipe_command, a8cat, BUFSIZ);
+
 	if(argc >= 2) {
 		if(strcmp(argv[1], "--help") == 0) {
 			print_help();
@@ -832,6 +838,12 @@ void open_output() {
 		outfile = stdout;
 		verbose(1, "using stdout for output");
 	} else {
+		const char *a8cat;
+		if((a8cat = getenv("A8CAT"))) {
+			verbose(1, "read A8CAT=%s from environment", a8cat);
+		} else {
+			verbose(1, "A8CAT not set in environment, using 'a8cat'");
+		}
 		verbose(1, "using pipe for output: %s", pipe_command);
 		outfile = popen(pipe_command, "w"); /* "wb" not allowed! */
 		/* we probably never see this error. popen() fails only if
diff --git a/listamsb.rst b/listamsb.rst
index a76c22b..902319b 100644
--- a/listamsb.rst
+++ b/listamsb.rst
@@ -223,6 +223,16 @@ continues processing.
   you see this warning, you'll also see *N* <unknown token *XX*>
   messages in the actual listing.
 
+ENVIRONMENT
+===========
+
+**A8CAT**
+
+  The path to the **a8cat**\(1) binary. Can be a full path or just
+  the executable name, in which case it will be searched for with the
+  normal **PATH** mechanism. If not set, *a8cat* is used. If there are
+  spaces or other metacharacters, they must be escaped.
+
 LIMITATIONS
 ===========