#include "ntheap.h"
#endif
-#ifdef HAVE_MMAP
-#include <unistd.h>
-#include <sys/mman.h>
-#endif
-
/* ------------------------------- */
/* TTY definitions */
/* ------------------------------- */
\f
/* Given FD, obtain pty buffer size. When no luck, a good guess is made,
- so that the function works even fd is not a pty. */
+ so that the function works even when fd is not a pty. */
int
get_pty_max_bytes (int fd)
{
- int pty_max_bytes;
-
+ /* DEC OSF 4.0 fpathconf returns 255, but xemacs hangs on long shell
+ input lines if we return 253. 252 is OK!. So let's leave a bit
+ of slack for the newline that xemacs will insert, and for those
+ inevitable vendor off-by-one-or-two-or-three bugs. */
+#define MAX_CANON_SLACK 10
+#define SAFE_MAX_CANON (127 - MAX_CANON_SLACK)
#if defined (HAVE_FPATHCONF) && defined (_PC_MAX_CANON)
- pty_max_bytes = fpathconf (fd, _PC_MAX_CANON);
- if (pty_max_bytes < 0)
+ {
+ int max_canon = fpathconf (fd, _PC_MAX_CANON);
+ return (max_canon < 0 ? SAFE_MAX_CANON :
+ max_canon > SAFE_MAX_CANON ? max_canon - MAX_CANON_SLACK :
+ max_canon);
+ }
+#elif defined (_POSIX_MAX_CANON)
+ return (_POSIX_MAX_CANON > SAFE_MAX_CANON ?
+ _POSIX_MAX_CANON - MAX_CANON_SLACK :
+ _POSIX_MAX_CANON);
+#else
+ return SAFE_MAX_CANON;
#endif
- pty_max_bytes = 250;
-
- /* Deduct one, to leave space for the eof. */
- pty_max_bytes--;
-
- return pty_max_bytes;
}
/* Figure out the eof character for the FD. */