diff --git a/src/process.c b/src/process.c index 67d1d3e425f..5f7408a9395 100644 --- a/src/process.c +++ b/src/process.c @@ -2189,8 +2189,14 @@ create_process (Lisp_Object process, char **new_argv, Lisp_Object current_dir) inchannel = p->open_fd[READ_FROM_SUBPROCESS]; forkout = p->open_fd[SUBPROCESS_STDOUT]; -#if defined(GNU_LINUX) && defined(F_SETPIPE_SZ) - fcntl (inchannel, F_SETPIPE_SZ, read_process_output_max); +#if defined(F_SETPIPE_SZ) && defined(F_GETPIPE_SZ) + /* If they requested larger reads than the default system pipe + capacity, try enlarging the capacity to match the request. */ + if (read_process_output_max > fcntl (inchannel, F_GETPIPE_SZ)) + { + int readmax = clip_to_bounds (1, read_process_output_max, INT_MAX); + fcntl (inchannel, F_SETPIPE_SZ, readmax); + } #endif }