Index: unix/sys-unix.c
===================================================================
--- unix/sys-unix.c	(revision 51208)
+++ unix/sys-unix.c	(working copy)
@@ -61,7 +61,7 @@
 attribute_hidden
 FILE *R_OpenInitFile(void)
 {
-    char buf[256], *home, *p = getenv("R_PROFILE_USER");
+    char buf[PATH_MAX], *home, *p = getenv("R_PROFILE_USER");
     FILE *fp;
 
     fp = NULL;
@@ -72,7 +72,7 @@
 	    return fp;
 	if((home = getenv("HOME")) == NULL)
 	    return NULL;
-	sprintf(buf, "%s/.Rprofile", home);
+	snprintf(buf, PATH_MAX, "%s/.Rprofile", home);
 	if((fp = R_fopen(buf, "r")))
 	    return fp;
     }
Index: main/startup.c
===================================================================
--- main/startup.c	(revision 51208)
+++ main/startup.c	(working copy)
@@ -52,10 +52,10 @@
 attribute_hidden
 FILE *R_OpenLibraryFile(const char *file)
 {
-    char buf[256];
+    char buf[PATH_MAX];
     FILE *fp;
 
-    snprintf(buf, 256, "%s/library/base/R/%s", R_Home, file);
+    snprintf(buf, PATH_MAX, "%s/library/base/R/%s", R_Home, file);
     fp = R_fopen(buf, "r");
     return fp;
 }
@@ -71,10 +71,10 @@
 attribute_hidden
 FILE *R_OpenSysInitFile(void)
 {
-    char buf[256];
+    char buf[PATH_MAX];
     FILE *fp;
 
-    snprintf(buf, 256, "%s/library/base/R/Rprofile", R_Home);
+    snprintf(buf, PATH_MAX, "%s/library/base/R/Rprofile", R_Home);
     fp = R_fopen(buf, "r");
     return fp;
 }
@@ -82,7 +82,7 @@
 attribute_hidden
 FILE *R_OpenSiteFile(void)
 {
-    char buf[256];
+    char buf[PATH_MAX];
     FILE *fp;
 
     fp = NULL;
@@ -91,10 +91,10 @@
 	    return fp;
 	if ((fp = R_fopen(getenv("RPROFILE"), "r")))
 	    return fp;
-	snprintf(buf, 256, "%s/etc/Rprofile.site", R_Home);
+	snprintf(buf, PATH_MAX, "%s/etc/Rprofile.site", R_Home);
 	if ((fp = R_fopen(buf, "r")))
 	    return fp;
-	/* snprintf(buf, 256, "%s/etc/Rprofile", R_Home);
+	/* snprintf(buf, PATH_MAX, "%s/etc/Rprofile", R_Home);
 	if ((fp = R_fopen(buf, "r")))
 	return fp; */
     }
Index: main/main.c
===================================================================
--- main/main.c	(revision 51208)
+++ main/main.c	(working copy)
@@ -862,9 +862,9 @@
     }
 
     if (strcmp(R_GUIType, "Tk") == 0) {
-	char buf[256];
+	char buf[PATH_MAX];
 
-	snprintf(buf, 256, "%s/library/tcltk/exec/Tk-frontend.R", R_Home);
+	snprintf(buf, PATH_MAX, "%s/library/tcltk/exec/Tk-frontend.R", R_Home);
 	R_LoadProfile(R_fopen(buf, "r"), R_GlobalEnv);
     }