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A couple of days ago I mentioned that I'm attempting to compile libmtp under MSYS2/MINGW64. Steps so far:

  • Install MSYS2
  • Do pacman -Syuu repeatedly after first start until everything is up to date
  • Install git: pacman -S git
  • Install base-devel for basic development utilities
  • install mingw-w64-x86_64-toolchain (as we need mingw-w64-x86_64-gcc to not get _spawnv errors, see
  • Install mingw-w64-x86_64-libiconv
  • Install mingw-w64-x86_64-libusb
  • Remember to run before running ./configure
  • Run make

Some useful MSYS2-specific things:

  • Use cd /c/ to get to the C: drive
  • pacman -S to install, -R to remove and -Ss to search
  • To access Windows path (e.g. to run node/npm, which can't be installed in MSYS2), add -use-full-path to the mingw64 app shortcut, or set environment variable MSYS2_PATH_TYPE to inherit

Now, after all of this I still got the following error:

unicode.c: In function 'utf16_to_utf8':
unicode.c:91:23: error: 'PTPParams' {aka 'struct _PTPParams'} has no member named 'cd_ucs2_to_locale'
   91 |   nconv = iconv(params->cd_ucs2_to_locale, &stringp, &convlen, &locp, &convmax);
      |                       ^~
unicode.c: In function 'utf8_to_utf16':
unicode.c:126:23: error: 'PTPParams' {aka 'struct _PTPParams'} has no member named 'cd_locale_to_ucs2'
  126 |   nconv = iconv(params->cd_locale_to_ucs2, &stringp, &convlen, &unip, &convmax);

Turns out, it's a known issue. Based on a potential fix linked to in that GitHub issue, I was able to write a fix for a different file:

diff --git a/src/unicode.c b/src/unicode.c
index 2adc94e..b14274b 100644
--- a/src/unicode.c
+++ b/src/unicode.c
@@ -87,12 +87,14 @@ char *utf16_to_utf8(LIBMTP_mtpdevice_t *device, const uint16_t *unicstr)
   size_t convmax = STRING_BUFFER_LENGTH*3;

+  #if defined(HAVE_ICONV) && defined(HAVE_LANGINFO_H)
   /* Do the conversion.  */
   nconv = iconv(params->cd_ucs2_to_locale, &stringp, &convlen, &locp, &convmax);
   if (nconv == (size_t) -1) {
     // Return partial string anyway.
     *locp = '\0';
+  #endif
   loclstr[STRING_BUFFER_LENGTH*3] = '\0';
   // Strip off any BOM, it's totally useless...
   if ((uint8_t) loclstr[0] == 0xEFU && (uint8_t) loclstr[1] == 0xBBU && (uint8_t) loclstr[2] == 0xBFU) {
@@ -121,7 +123,7 @@ uint16_t *utf8_to_utf16(LIBMTP_mtpdevice_t *device, const char *localstr)

+  #if defined(HAVE_ICONV) && defined(HAVE_LANGINFO_H)
   /* Do the conversion.  */
   nconv = iconv(params->cd_locale_to_ucs2, &stringp, &convlen, &unip, &convmax);

@@ -130,6 +132,7 @@ uint16_t *utf8_to_utf16(LIBMTP_mtpdevice_t *device, const char *localstr)
     unip[0] = '\0';
     unip[1] = '\0';
+  #endif
   // make sure the string is null terminated
   unicstr[STRING_BUFFER_LENGTH*2] = '\0';
   unicstr[STRING_BUFFER_LENGTH*2+1] = '\0';

Lo and behold, I got it to compile!

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