function to change working directory

src/C_routines.c

@@ -11,9 +11,9 @@
 
 int isdirectory_c(const char *dir){
   struct stat statbuf;
-  if(stat(dir, &statbuf) != 0)
-    return 0;
-  return S_ISDIR(statbuf.st_mode);
+  if(stat(dir, &statbuf) != 0)                                                                      /* error */
+    return 0;                                                                                       /* return "NO, this is not a directory" */
+  return S_ISDIR(statbuf.st_mode);                                                                  /* 1 => is directory, 0 => this is NOT a directory */
 }
 
 
@@ -29,7 +29,7 @@ void getcurrentworkdir_c(char cwd[], int *stat ){
 }
 
 
-void gethostname_c(char hostname[], int *stat ){
+void gethostname_c(char hostname[], int *stat){
   char hostname_tmp[1024];
   if(gethostname(hostname_tmp, sizeof(hostname_tmp)) == 0){
     strcpy(hostname,hostname_tmp);
@@ -39,3 +39,8 @@ void gethostname_c(char hostname[], int *stat ){
     *stat = 1;
   }
 }
+
+
+int chdir_c(const char *dir){
+  return chdir(dir);
+}

src/system_routines.f90

@@ -10,11 +10,12 @@ module system_routines
  public :: &
    isDirectory, &
    getCWD, &
-   getHostName
+   getHostName, &
+   setCWD
 
 interface
 
- function  isDirectory_C(path) BIND(C)
+ function isDirectory_C(path) bind(C)
    use, intrinsic :: ISO_C_Binding, only: &
      C_INT, &
      C_CHAR
@@ -38,6 +39,14 @@ interface
    integer(C_INT),intent(out)         :: stat
   end subroutine getHostName_C
 
+ function chdir_C(path) bind(C)
+   use, intrinsic :: ISO_C_Binding, only: &
+     C_INT, &
+     C_CHAR
+   integer(C_INT) :: chdir_C
+   character(kind=C_CHAR), dimension(1024), intent(in) :: path                                      ! C string is an array
+ end function chdir_C
+
 end interface
 
 
@@ -123,5 +132,27 @@ logical function getHostName(str)
 
 end function getHostName
 
+!--------------------------------------------------------------------------------------------------
+!> @brief changes the current working directory
+!--------------------------------------------------------------------------------------------------
+logical function setCWD(path)
+  use, intrinsic :: ISO_C_Binding, only: &
+    C_INT, &
+    C_CHAR, &
+    C_NULL_CHAR
+
+  implicit none
+  character(len=*), intent(in) :: path
+  character(kind=C_CHAR), dimension(1024) :: strFixedLength                                         ! C string is an array
+  integer :: i
+
+  strFixedLength = repeat(C_NULL_CHAR,len(strFixedLength))
+  do i=1,len(path)                                                                                  ! copy array components
+    strFixedLength(i)=path(i:i)
+  enddo
+  setCWD=merge(.True.,.False.,chdir_C(strFixedLength) /= 0_C_INT)
+
+end function setCWD
+
 end module system_routines