From: Michael Kerrisk <mtk.manpages@gmail.com>
Date: Sun, 18 Jun 2017 09:15:34 +0000 (+0200)
Subject: fpathconf.3: Rework RETURN VALUE description to add more detail
X-Git-Tag: man-pages-4.12~43
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=081a3c719b9e0957529837ad94e40adb890a2e2e;p=thirdparty%2Fman-pages.git

fpathconf.3: Rework RETURN VALUE description to add more detail

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
---

diff --git a/man3/fpathconf.3 b/man3/fpathconf.3
index 2a7b37de7b..b95006cb38 100644
--- a/man3/fpathconf.3
+++ b/man3/fpathconf.3
@@ -158,14 +158,43 @@ or
 .I path
 must refer to a terminal.
 .SH RETURN VALUE
-The limit is returned, if one exists.
-If the system does not have a
-limit for the requested resource, \-1 is returned, and
+The return value of these functions is one of the following:
+.IP * 3
+On error, \-1 is returned and
 .I errno
-is unchanged.
-If there is an error, \-1 is returned, and
+is set to indicate the cause of the error
+(for example,
+.BR EINVAL ,
+indicating that
+.I name
+is invalid).
+.IP *
+If
+.I name
+corresponds to a maximum or minimum limit, and that limit is indeterminate,
+\-1 is returned and
+.I errno
+is not changed.
+(To distinguish an indeterminate limit from an error, set
+.I errno
+to zero before the call, and then check whether
 .I errno
-is set to reflect the nature of the error.
+is nonzero when \-1 is returned.)
+.IP *
+If
+.I name
+corresponds to an option,
+a positive value is returned if the option is supported,
+and \-1 is returned if the option is not supported.
+.IP *
+Otherwise,
+the current value of the option or limit is returned.
+This value will not be more restrictive than
+the corresponding value that was described to the application in
+.I <unistd.h>
+or
+.I <limits.h>
+when the application was compiled.
 .SH ATTRIBUTES
 For an explanation of the terms used in this section, see
 .BR attributes (7).