When hugs's standard input is not a tty, this patch stops it prompting or attempting to use readline. It also disables $$ in that situation; this could be changed if desired, but is probably the right thing. If it is put it in, the --with-readline option of configure can probably be ditched (i.e. set USE_READLINE if editline or readline is available). Index: src/input.c =================================================================== RCS file: /home/cvs/root/hugs98/src/input.c,v retrieving revision 1.43 diff -u -r1.43 input.c --- src/input.c 2002/06/14 14:41:10 1.43 +++ src/input.c 2002/07/18 15:58:05 @@ -264,6 +264,7 @@ #define SCRIPTFILE 2 /* - script file */ #define PROJFILE 3 /* - project file */ #define STRING 4 /* - string buffer? */ +#define NOKEYBOARD 5 /* - standard input, but not a tty */ static Int reading = NOTHING; @@ -322,6 +323,12 @@ hereState = START; #endif +#ifdef HAVE_ISATTY + if (!isatty(fileno(stdin))) { /* not reading from a tty: */ + reading = NOKEYBOARD; /* don't prompt or try readline */ + return; + } +#endif #if USE_READLINE /* Paranoid freeing code supplied by Sverker Nilsson (sverker@opq.se) * avoids accidentally freeing currentLine twice. @@ -607,6 +614,9 @@ c1 = ' '; } } + } + else if (reading==NOKEYBOARD) { + c1 = c0=='\n' ? EOF : getc(stdin); } else if (reading==STRING) { c1 = (unsigned char) *nextStringChar++;