diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/w32.c | 15 | ||||
| -rw-r--r-- | src/w32proc.c | 15 |
2 files changed, 17 insertions, 13 deletions
diff --git a/src/w32.c b/src/w32.c index e93aaab9ca1..c848b33b2af 100644 --- a/src/w32.c +++ b/src/w32.c @@ -8469,13 +8469,14 @@ _sys_read_ahead (int fd) { rc = _read (fd, &cp->chr, sizeof (char)); - /* Give subprocess time to buffer some more output for us before - reporting that input is available; we need this because Windows 95 - connects DOS programs to pipes by making the pipe appear to be - the normal console stdout - as a result most DOS programs will - write to stdout without buffering, ie. one character at a - time. Even some W32 programs do this - "dir" in a command - shell on NT is very slow if we don't do this. */ + /* Optionally give subprocess time to buffer some more output + for us before reporting that input is available; we may need + this because Windows 9X connects DOS programs to pipes by + making the pipe appear to be the normal console stdout -- as + a result most DOS programs will write to stdout without + buffering, i.e., one character at a time. Even some W32 + programs do this -- "dir" in a command shell on NT is very + slow if we don't do this. */ if (rc > 0) { int wait = w32_pipe_read_delay; diff --git a/src/w32proc.c b/src/w32proc.c index 28d7b6611f6..5934669c363 100644 --- a/src/w32proc.c +++ b/src/w32proc.c @@ -3763,14 +3763,17 @@ them blocking when trying to access unmounted drives etc. */); DEFVAR_INT ("w32-pipe-read-delay", w32_pipe_read_delay, doc: /* Forced delay before reading subprocess output. -This is done to improve the buffering of subprocess output, by -avoiding the inefficiency of frequently reading small amounts of data. +This may need to be done to improve the buffering of subprocess output, +by avoiding the inefficiency of frequently reading small amounts of data. +Typically needed only with DOS programs on Windows 9X; set to 50 if +throughput with such programs is slow. If positive, the value is the number of milliseconds to sleep before -reading the subprocess output. If negative, the magnitude is the number -of time slices to wait (effectively boosting the priority of the child -process temporarily). A value of zero disables waiting entirely. */); - w32_pipe_read_delay = 50; +signaling that output from a subprocess is ready to be read. +If negative, the value is the number of time slices to wait (effectively +boosting the priority of the child process temporarily). +A value of zero disables waiting entirely. */); + w32_pipe_read_delay = 0; DEFVAR_INT ("w32-pipe-buffer-size", w32_pipe_buffer_size, doc: /* Size of buffer for pipes created to communicate with subprocesses. |