sys: hard_link_count

Author: scivision

+stdlib/+sys/hard_link_count.m

@@ -0,0 +1,29 @@
+%% SYS.HARD_LINK_COUNT number of hard links to file
+%
+% Powershell is 0, 1, or 2
+
+function n = hard_link_count(file)
+
+if ~stdlib.exists(file)
+  n = 0;
+  return
+end
+
+if ispc()
+  cmd = sprintf('pwsh -c "(Get-Item ''%s'').LinkType"', file);
+elseif ismac()
+  cmd = sprintf('stat -f %%l ''%s''', file);
+else
+  cmd = sprintf('stat -c %%h ''%s''', file);
+end
+
+[status, output] = system(cmd);
+if status == 0
+  if ispc()
+    n = 1 + startsWith(output, "HardLink");
+  else
+    n = str2double(output);
+  end
+end
+
+end

+stdlib/hard_link_count.m

@@ -1,14 +1,15 @@
 %% HARD_LINK_COUNT get the number of hard links to a file
 %
 %
-% Ref:
+%% Java backend references:
+%
 % * https://docs.oracle.com/en/java/javase/21/docs/api/java.base/java/nio/file/Files.html#getPosixFileAttributes(java.nio.file.Path,java.nio.file.LinkOption...)
 % * https://docs.oracle.com/javase/tutorial/essential/io/links.html
 
 function c = hard_link_count(file, backend)
 arguments
   file {mustBeTextScalar}
-  backend (1,:) string = ["java", "python"]
+  backend (1,:) string = ["java", "python", "sys"]
 end
 
 fun = hbackend(backend, "hard_link_count");

+stdlib/has_java.m

@@ -1,4 +1,6 @@
 %% HAS_JAVA detect if JVM is available
+%
+% Ref: https://www.mathworks.com/help/matlab/ref/usejava.html
 
 function y = has_java()
 

test/TestDisk.m

@@ -7,11 +7,10 @@
 properties (TestParameter)
 Ps = {".", "", "/", getenv("SystemDrive"), "not-exist"}
 Po = {mfilename("fullpath") + ".m", pwd(), ".", "", "not-exist"}
-id_fun = {'sys', 'java', 'python'}
+java_python_sys = {'sys', 'java', 'python'}
 id_name = {"inode", "device"}
 all_fun = {'sys', 'dotnet', 'java', 'python'}
 disk_ac_name = {'disk_available', 'disk_capacity'}
-hl_fun = {'java', 'python'}
 is_remove = {'dotnet', 'sys'}
 py_sys = {'python', 'sys'}
 end
@@ -77,14 +76,14 @@ function test_is_mount(tc, py_sys)
 end
 
 
-function test_hard_link_count(tc, hl_fun)
+function test_hard_link_count(tc, java_python_sys)
 fname = "hard_link_count";
-n = "stdlib." + hl_fun + "." + fname;
+n = "stdlib." + java_python_sys + "." + fname;
 h = str2func("stdlib." + fname);
 tc.assertNotEmpty(which(n))
 P = mfilename("fullpath") + ".m";
 try
-  r = h(P, hl_fun);
+  r = h(P, java_python_sys);
   tc.verifyGreaterThanOrEqual(r, 1)
 catch e
   tc.verifyEqual(e.identifier, 'stdlib:hbackend:NameError', e.message)
@@ -128,16 +127,16 @@ function test_remove_file(tc)
 end
 
 
-function test_inode_device(tc, id_fun, id_name)
-n = "stdlib." + id_fun + "." + id_name;
+function test_inode_device(tc, java_python_sys, id_name)
+n = "stdlib." + java_python_sys + "." + id_name;
 h = str2func("stdlib." + id_name);
 tc.assertNotEmpty(which(n))
 
 try
-    ip = h(pwd(), id_fun);
+    ip = h(pwd(), java_python_sys);
     tc.verifyClass(ip, 'uint64')
     tc.verifyGreaterThan(ip, 0)
-    tc.verifyEqual(h(".", id_fun), ip)
+    tc.verifyEqual(h(".", java_python_sys), ip)
 catch e
   tc.verifyEqual(e.identifier, 'stdlib:hbackend:NameError', e.message)
 end