It appears that since the misc_conv conversation module's read_string()
function is using unbuffered io and is reading rather large chunks.
This means that the misc_conv conversation may be eating stdin that
was not intended for it. For example, using misc_conv to retrieve
a user's name or password, then fork()ing or exec()ing another process.
If you're piping input into this program, some portion of the input will
be eaten by read_string() before it ever reaches the destination.
Here's a small diff to misc_conv to read a line at a time.
Rob
--- misc_conv.c 2002/03/27 06:18:21 1.9
+++ misc_conv.c 2002/05/30 17:27:59
@@ -181,7 +181,13 @@
D(("<failed to set alarm>"));
break;
} else {
- nc = read(STDIN_FILENO, line, INPUTSIZE-1);
+ for( nc = 0; (nc < INPUTSIZE) && (line[nc?nc-1:0] != '\n'); nc++ ) {
+ if( read(STDIN_FILENO, line+nc, 1) != 1 ) {
+ break;
+ }
+ }
+ line[nc] = '\0';
+
if (have_term) {
(void) tcsetattr(STDIN_FILENO, TCSADRAIN, &term_before);
if (!echo || expired) /* do we need a newline? */
