From 618170baf3dc7295d157ab0ae891488744868719 Mon Sep 17 00:00:00 2001
From: Gerhard Rieger <gerhard@dest-unreach.org>
Date: Mon, 29 Sep 2008 21:16:41 +0200
Subject: [PATCH] HP-UX port: unsetenv() might not exist

---
 config.h.in  | 5 ++++-
 configure.in | 3 +++
 sycls.c      | 2 ++
 sysutils.c   | 4 ++++
 4 files changed, 13 insertions(+), 1 deletion(-)

diff --git a/config.h.in b/config.h.in
index 259a942..46d12c6 100644
--- a/config.h.in
+++ b/config.h.in
@@ -331,7 +331,7 @@
 /* Define if you have struct ifreq.ifr_index */
 #undef HAVE_STRUCT_IFREQ_IFR_INDEX
 
-/* Define if you have struct ifreq.ifr_ifindex */
+/* Define if you have struct ifreq.ifr_ifindex; not on HPUX */
 #undef HAVE_STRUCT_IFREQ_IFR_IFINDEX
 
 /* Define if your struct sockaddr has sa_len */
@@ -364,6 +364,9 @@
 /* Define if you have the setenv function */
 #undef HAVE_SETENV
 
+/* Define if you have the unsetenv function. not on HP-UX */
+#undef HAVE_UNSETENV
+
 /* Define if you have the flock function */
 #undef HAVE_FLOCK
 
diff --git a/configure.in b/configure.in
index b84d510..61dd284 100644
--- a/configure.in
+++ b/configure.in
@@ -1198,6 +1198,9 @@ dnl Search for setenv()
 AC_CHECK_FUNC(setenv, AC_DEFINE(HAVE_SETENV),
 	AC_CHECK_LIB(isode, setenv, [LIBS="-lisode $LIBS"]))
 
+dnl Search for unsetenv()
+AC_CHECK_FUNC(unsetenv, AC_DEFINE(HAVE_UNSETENV))
+
 
 dnl Run time checks
 
diff --git a/sycls.c b/sycls.c
index e9b004f..fa9f1f9 100644
--- a/sycls.c
+++ b/sycls.c
@@ -1459,6 +1459,7 @@ int Setenv(const char *name, const char *value, int overwrite) {
    return result;
 }
 
+#if HAVE_UNSETENV
 /* on Linux it returns int but on FreeBSD void.
    we do not expect many errors, so we take void which works on all systems. */
 void Unsetenv(const char *name) {
@@ -1470,6 +1471,7 @@ void Unsetenv(const char *name) {
    errno = _errno;
    return;
 }
+#endif
 
 #if WITH_READLINE
 
diff --git a/sysutils.c b/sysutils.c
index ed1a1fa..f9512e7 100644
--- a/sysutils.c
+++ b/sysutils.c
@@ -550,7 +550,9 @@ int xiosetenv(const char *varname, const char *value, int overwrite) {
    if (Setenv(envname, value, overwrite) < 0) {
       Warn3("setenv(\"%s\", \"%s\", 1): %s",
 	    envname, value, strerror(errno));
+#if HAVE_UNSETENV
       Unsetenv(envname);      /* dont want to have a wrong value */
+#endif
       return -1;
    }
    return 0;
@@ -579,7 +581,9 @@ int xiosetenv2(const char *varname, const char *varname2, const char *value,
    if (Setenv(envname, value, overwrite) < 0) {
       Warn3("setenv(\"%s\", \"%s\", 1): %s",
 	    envname, value, strerror(errno));
+#if HAVE_UNSETENV
       Unsetenv(envname);      /* dont want to have a wrong value */
+#endif
       return -1;
    }
    return 0;