diff --git a/proc/diskstats.h b/proc/diskstats.h
index 83b8c479..dd718910 100644
--- a/proc/diskstats.h
+++ b/proc/diskstats.h
@@ -23,9 +23,9 @@
 #ifndef PROCPS_DISKSTATS_H
 #define PROCPS_DISKSTATS_H
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum diskstats_item {
     DISKSTATS_noop,                 //        ( never altered )
@@ -126,5 +126,7 @@ struct diskstats_stack **procps_diskstats_sort (
     enum diskstats_item sortitem,
     enum diskstats_sort_order order);
 
-__END_DECLS
+#ifdef __cplusplus
+}
+#endif
 #endif
diff --git a/proc/meminfo.h b/proc/meminfo.h
index 1e363846..238221c6 100644
--- a/proc/meminfo.h
+++ b/proc/meminfo.h
@@ -19,9 +19,9 @@
 #ifndef PROCPS_MEMINFO_H
 #define PROCPS_MEMINFO_H
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum meminfo_item {
     MEMINFO_noop,                  //        ( never altered )
@@ -171,5 +171,7 @@ struct meminfo_stack *procps_meminfo_select (
     enum meminfo_item *items,
     int numitems);
 
-__END_DECLS
+#ifdef __cplusplus
+}
+#endif
 #endif
diff --git a/proc/namespace.h b/proc/namespace.h
index 2885d8d5..f57b060d 100644
--- a/proc/namespace.h
+++ b/proc/namespace.h
@@ -23,7 +23,9 @@
 #ifndef PROC_NAMESPACE_H
 #define PROC_NAMESPACE_H
 
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum namespace_type {
     PROCPS_NS_IPC,
@@ -44,6 +46,8 @@ const char *procps_ns_get_name(const int id);
 int procps_ns_get_id(const char *name);
 
 int procps_ns_read_pid(const int pid, struct procps_namespaces *nsp);
-__END_DECLS
 
+#ifdef __cplusplus
+}
+#endif
 #endif
diff --git a/proc/pids.h b/proc/pids.h
index f6c15810..c183c88a 100644
--- a/proc/pids.h
+++ b/proc/pids.h
@@ -23,9 +23,9 @@
 #ifndef PROCPS_PIDS_H
 #define PROCPS_PIDS_H
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum pids_item {
     PIDS_noop,              //        ( never altered )
@@ -233,5 +233,7 @@ struct pids_stack **procps_pids_sort (
     enum pids_item sortitem,
     enum pids_sort_order order);
 
-__END_DECLS
+#ifdef __cplusplus
+}
+#endif
 #endif
diff --git a/proc/slabinfo.h b/proc/slabinfo.h
index e0c549e9..7454515c 100644
--- a/proc/slabinfo.h
+++ b/proc/slabinfo.h
@@ -23,9 +23,9 @@
 #ifndef PROCPS_SLABINFO_H
 #define PROCPS_SLABINFO_H
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum slabinfo_item {
     SLABINFO_noop,            //       ( never altered )
@@ -130,5 +130,7 @@ struct slabinfo_stack **procps_slabinfo_sort (
     enum slabinfo_item sortitem,
     enum slabinfo_sort_order order);
 
-__END_DECLS
+#ifdef __cplusplus
+}
+#endif
 #endif
diff --git a/proc/stat.h b/proc/stat.h
index 6151e282..5682773c 100644
--- a/proc/stat.h
+++ b/proc/stat.h
@@ -19,9 +19,9 @@
 #ifndef PROCPS_STAT_H
 #define PROCPS_STAT_H
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum stat_item {
     STAT_noop,                    //        ( never altered )
@@ -154,5 +154,7 @@ struct stat_stack **procps_stat_sort (
     enum stat_item sortitem,
     enum stat_sort_order order);
 
-__END_DECLS
+#ifdef __cplusplus
+}
+#endif
 #endif
diff --git a/proc/sysinfo.h b/proc/sysinfo.h
index 167f892b..9bd8bc55 100644
--- a/proc/sysinfo.h
+++ b/proc/sysinfo.h
@@ -3,13 +3,16 @@
 #include <sys/types.h>
 #include <dirent.h>
 
-#include <features.h>
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 long procps_cpu_count(void);
 long procps_hertz_get(void);
 int procps_loadavg(double *av1, double *av5, double *av15);
 unsigned int procps_pid_length(void);
 
-__END_DECLS
-#endif /* SYSINFO_H */
+#ifdef __cplusplus
+}
+#endif
+#endif
diff --git a/proc/uptime.h b/proc/uptime.h
index 8d00854d..dc14be8c 100644
--- a/proc/uptime.h
+++ b/proc/uptime.h
@@ -25,13 +25,15 @@
 #ifndef PROC_UPTIME_H
 #define PROC_UPTIME_H
 
-#include <features.h>
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 int procps_uptime(double *uptime_secs, double *idle_secs);
 char *procps_uptime_sprint(void);
 char *procps_uptime_sprint_short(void);
 
-__END_DECLS
-
+#ifdef __cplusplus
+}
+#endif
 #endif
diff --git a/proc/version.h b/proc/version.h
index 3cde808c..dd9e7d77 100644
--- a/proc/version.h
+++ b/proc/version.h
@@ -23,10 +23,9 @@
 #ifndef PROC_VERSION_H
 #define PROC_VERSION_H
 
-#include <features.h>
-__BEGIN_DECLS
-
-int procps_linux_version(void);
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 /* Convenience macros for composing/decomposing version codes */
 #define LINUX_VERSION(x,y,z)   (0x10000*((x)&0x7fff) + 0x100*((y)&0xff) + ((z)&0xff))
@@ -34,6 +33,9 @@ int procps_linux_version(void);
 #define LINUX_VERSION_MINOR(x) (((x)>> 8) & 0xFF)
 #define LINUX_VERSION_PATCH(x) ( (x)      & 0xFF)
 
-__END_DECLS
+int procps_linux_version(void);
 
-#endif	/* PROC_VERSION_H */
+#ifdef __cplusplus
+}
+#endif
+#endif
diff --git a/proc/vmstat.h b/proc/vmstat.h
index 98e0cc69..4db14b09 100644
--- a/proc/vmstat.h
+++ b/proc/vmstat.h
@@ -24,9 +24,9 @@
 #ifndef PROCPS_VMSTAT_H
 #define PROCPS_VMSTAT_H
 
-#include <sys/cdefs.h>
-
-__BEGIN_DECLS
+#ifdef __cplusplus
+extern "C" {
+#endif
 
 enum vmstat_item {
     VMSTAT_noop,                                 //       ( never altered )
@@ -308,5 +308,7 @@ struct vmstat_stack *procps_vmstat_select (
     enum vmstat_item *items,
     int numitems);
 
-__END_DECLS
+#ifdef __cplusplus
+}
+#endif
 #endif