global variable Infile_Path, which contains the

input netlist file path

src/frontend/inp.c

@@ -1146,7 +1146,7 @@ com_source(wordlist *wl)
     FILE *fp, *tp;
     char buf[BSIZE_SP];
     bool inter;
-    char *tempfile = NULL;
+    char *tempfile = NULL, *firstfile;
 
     wordlist *owl = wl;
     size_t n;
@@ -1154,6 +1154,8 @@ com_source(wordlist *wl)
     inter = cp_interactive;
     cp_interactive = FALSE;
 
+    firstfile = wl->wl_word;
+
     if (wl->wl_next) {
         /* There are several files -- put them into a temp file  */
         tempfile = smktemp("sp");
@@ -1189,8 +1191,13 @@ com_source(wordlist *wl)
     /* Don't print the title if this is a spice initialisation file. */
     if (ft_nutmeg || substring(INITSTR, owl->wl_word) || substring(ALT_INITSTR, owl->wl_word))
         inp_spsource(fp, TRUE, tempfile ? NULL : wl->wl_word, FALSE);
-    else
+    else {
+        /* Save path name for use in XSPICE fopen_with_path() */
+        if (Infile_Path)
+            tfree(Infile_Path);
+        Infile_Path = ngdirname(firstfile);
         inp_spsource(fp, FALSE, tempfile ? NULL : wl->wl_word, FALSE);
+    }
 
     cp_interactive = inter;
     if (tempfile)

src/include/ngspice/ngspice.h

@@ -245,6 +245,7 @@ extern char *Spice_Path;
 extern char *Help_Path;
 extern char *Lib_Path;
 extern char *Inp_Path;
+extern char *Infile_Path;
 
 #ifdef TCL_MODULE
 

src/main.c

@@ -43,6 +43,7 @@
 #include "spicelib/analysis/analysis.h"
 #include "misc/ivars.h"
 #include "misc/misc_time.h"
+#include "misc/util.h"
 
 #if defined(HAS_WINGUI) || defined(_MSC_VER) || defined(__MINGW32__)
 # include "misc/mktemp.h"
@@ -113,6 +114,8 @@ char *errRtn;     /* name of the routine declaring error */
 char *errMsg = NULL;     /* descriptive message about what went wrong */
 char *cp_program; /* program name 'ngspice' */
 
+char *Infile_Path = NULL; /* Path to netlist input file */
+
 
 /* Globals definitions for Machine Accuracy Limits
  * (needed by CIDER)
@@ -1217,6 +1220,9 @@ main(int argc, char **argv)
             while (optind < argc) {
                 char *arg = argv[optind++];
                 FILE *tp;
+                /* Copy the the path of the first filename only */
+                if (!Infile_Path)
+                    Infile_Path = ngdirname(arg);
 
                 /* Copy all the arguments into the temporary file */
                 tp = fopen(arg, "r");