I wrote:
> Pavel Stehule <pavel.steh...@gmail.com> writes:
>> Except for testing, using pager in non-interactive mode makes no sense.
> Agreed. Let's solve this by inserting isatty tests in psql, rather
> than hacking the test environment.
Here's a proposed patch for this. I noticed that another memo the
PSQL_WATCH_PAGER patch had not gotten was the lesson learned in
commit 18f8f784c, namely that it's a good idea to ignore empty
or all-blank settings.
regards, tom lane
diff --git a/src/bin/psql/command.c b/src/bin/psql/command.c
index 97f7d97220..607a57715a 100644
--- a/src/bin/psql/command.c
+++ b/src/bin/psql/command.c
@@ -5197,14 +5197,20 @@ do_watch(PQExpBuffer query_buf, double sleep, int iter)
/*
* For \watch, we ignore the size of the result and always use the pager
- * if PSQL_WATCH_PAGER is set. We also ignore the regular PSQL_PAGER or
- * PAGER environment variables, because traditional pagers probably won't
- * be very useful for showing a stream of results.
+ * as long as we're talking to a terminal and "\pset pager" is enabled.
+ * However, we'll only use the pager identified by PSQL_WATCH_PAGER. We
+ * ignore the regular PSQL_PAGER or PAGER environment variables, because
+ * traditional pagers probably won't be very useful for showing a stream
+ * of results.
*/
#ifndef WIN32
pagerprog = getenv("PSQL_WATCH_PAGER");
+ /* if variable is empty or all-white-space, don't use pager */
+ if (pagerprog && strspn(pagerprog, " \t\r\n") == strlen(pagerprog))
+ pagerprog = NULL;
#endif
- if (pagerprog && myopt.topt.pager)
+ if (pagerprog && myopt.topt.pager &&
+ isatty(fileno(stdin)) && isatty(fileno(stdout)))
{
fflush(NULL);
disable_sigpipe_trap();
