This patch makes the "/ID" field optional. If the environment variable GS_GENERATE_UUIDS is set to "0" or "no", it will not write out the "/ID" field (if that's permissible). Upstream does not want to do this. See: https://bugs.ghostscript.com/show_bug.cgi?id=698208 diff -ur orig/gnu-ghostscript-9.14.0/devices/vector/gdevpdf.c gnu-ghostscript-9.14.0/devices/vector/gdevpdf.c --- orig/gnu-ghostscript-9.14.0/devices/vector/gdevpdf.c 2017-07-09 23:30:28.960479189 +0200 +++ gnu-ghostscript-9.14.0/devices/vector/gdevpdf.c 2017-07-09 23:34:34.306524488 +0200 @@ -1580,8 +1580,11 @@ * +1 for the linearisation dict and +1 for the primary hint stream. */ linear_params->FirsttrailerOffset = gp_ftell_64(linear_params->Lin_File.file); - gs_sprintf(LDict, "\ntrailer\n<>\nstartxref\r\n0\n%%%%EOF\n \n", - linear_params->LastResource + 3, pdev->ResourceUsage[linear_params->Info_id].NewObjectNumber, pdev->ResourceUsage[linear_params->Catalog_id].NewObjectNumber, fileID, fileID, 0); + gs_sprintf(LDict, "\ntrailer\n<LastResource + 3, pdev->ResourceUsage[linear_params->Info_id].NewObjectNumber, pdev->ResourceUsage[linear_params->Catalog_id].NewObjectNumber); + if (pdev->OwnerPassword.size > 0 || !(!getenv("GS_GENERATE_UUIDS") || (strcasecmp(getenv("GS_GENERATE_UUIDS"), "0") != 0 && strcasecmp(getenv("GS_GENERATE_UUIDS"), "no") != 0))) /* ID is mandatory when encrypting */ + gs_sprintf(LDict, "/ID[%s%s]", fileID, fileID); + gs_sprintf(LDict, "/Prev %d>>\nstartxref\r\n0\n%%%%EOF\n \n", 0); fwrite(LDict, strlen(LDict), 1, linear_params->Lin_File.file); /* Write document catalog (Part 4) */ @@ -2102,8 +2105,11 @@ * in the missing values. */ code = gp_fseek_64(linear_params->sfile, linear_params->FirsttrailerOffset, SEEK_SET); - gs_sprintf(LDict, "\ntrailer\n<>\nstartxref\r\n0\n%%%%EOF\n", - linear_params->LastResource + 3, pdev->ResourceUsage[linear_params->Info_id].NewObjectNumber, pdev->ResourceUsage[linear_params->Catalog_id].NewObjectNumber, fileID, fileID, mainxref); + gs_sprintf(LDict, "\ntrailer\n<LastResource + 3, pdev->ResourceUsage[linear_params->Info_id].NewObjectNumber, pdev->ResourceUsage[linear_params->Catalog_id].NewObjectNumber); + if (pdev->OwnerPassword.size > 0 || !(!getenv("GS_GENERATE_UUIDS") || (strcasecmp(getenv("GS_GENERATE_UUIDS"), "0") != 0 || strcasecmp(getenv("GS_GENERATE_UUIDS"), "no") != 0))) /* ID is mandatory when encrypting */ + gs_sprintf(LDict, "/ID[%s%s]", fileID, fileID); + gs_sprintf(LDict, "/Prev %"PRId64">>\nstartxref\r\n0\n%%%%EOF\n", mainxref); fwrite(LDict, strlen(LDict), 1, linear_params->sfile); code = gp_fseek_64(linear_params->sfile, pdev->ResourceUsage[HintStreamObj].LinearisedOffset, SEEK_SET); @@ -2674,10 +2680,12 @@ stream_puts(s, "trailer\n"); pprintld3(s, "<< /Size %ld /Root %ld 0 R /Info %ld 0 R\n", pdev->next_id, Catalog_id, Info_id); - stream_puts(s, "/ID ["); - psdf_write_string(pdev->strm, pdev->fileID, sizeof(pdev->fileID), 0); - psdf_write_string(pdev->strm, pdev->fileID, sizeof(pdev->fileID), 0); - stream_puts(s, "]\n"); + if (pdev->OwnerPassword.size > 0 || !(!getenv("GS_GENERATE_UUIDS") || (strcasecmp(getenv("GS_GENERATE_UUIDS"), "0") != 0 || strcasecmp(getenv("GS_GENERATE_UUIDS"), "no") != 0))) { /* ID is mandatory when encrypting */ + stream_puts(s, "/ID ["); + psdf_write_string(pdev->strm, pdev->fileID, sizeof(pdev->fileID), 0); + psdf_write_string(pdev->strm, pdev->fileID, sizeof(pdev->fileID), 0); + stream_puts(s, "]\n"); + } if (pdev->OwnerPassword.size > 0) { pprintld1(s, "/Encrypt %ld 0 R ", Encrypt_id); } Nur in gnu-ghostscript-9.14.0/devices/vector: gdevpdf.c.orig.