sg_logs: tweak the meaning of --list option; sg_opcodes: cleanup error reporting

git-svn-id: https://svn.bingwo.ca/repos/sg3_utils/trunk@925 6180dd3e-e324-4e3e-922d-17de1ae2f315

7 files changed, 125 insertions, 87 deletions

diff --git a/ChangeLog b/ChangeLog
index b62f9265..12c01bdf 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -2,12 +2,15 @@ Each utility has its own version number, date of last change and
 some description at the top of its ".c" file. All utilities in the main
 directory have their own "man" pages. There is also a sg3_utils man page.
 
-Changelog for pre-release sg3_utils-1.48 [20211203] [svn: r924]
+Changelog for pre-release sg3_utils-1.48 [20211222] [svn: r925]
   - sg_z_act_query: new utility for sending either a
     Zone activate or Zone query command
   - sg_rep_zones: add Report zone starting LBA granularity
     field in REPORT ZONES response [zbc2r12]
   - sg_decode_sense: add --nodecode option
+  - sg_logs: tweak the meaning of --list option to more closely
+    reflect the contents of log pages 0x0 and 0x0,0xff
+  - sg_opcodes: cleanup error reporting
   - initialize all sense buffers to 0
   - rework main README file
   - rev 921+922 are bugfix revs on release 1.47 [r919,920]
diff --git a/debian/changelog b/debian/changelog
index a28dfbcc..2e945a02 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -2,7 +2,7 @@ sg3-utils (1.48-0.1) unstable; urgency=low
 
   * New upstream version
 
- -- Douglas Gilbert <dgilbert@interlog.com>  Fri, 03 Dec 2021 19:00:00 -0500
+ -- Douglas Gilbert <dgilbert@interlog.com>  Wed, 22 Dec 2021 01:00:00 -0500
 
 sg3-utils (1.47-0.1) unstable; urgency=low
 
diff --git a/doc/sg3_utils.8 b/doc/sg3_utils.8
index 25a0d0b6..954126f6 100644
--- a/doc/sg3_utils.8
+++ b/doc/sg3_utils.8
@@ -445,7 +445,7 @@ number returned as the exit status (7 bits).
 a transport error has occurred. This will either be in the driver (e.g. HBA
 driver) or in the interconnect between the host (initiator) and the
 device (target).  For example in SAS an expander can run out of paths and
-thus be unable to return the user data for a READ command.
+thus be unable to return the user data from a READ command.
 .TP
 .B 36
 no error has occurred plus the utility wants to convey a boolean value
diff --git a/doc/sg_logs.8 b/doc/sg_logs.8
index 43fd1901..7df65b6a 100644
--- a/doc/sg_logs.8
+++ b/doc/sg_logs.8
@@ -1,4 +1,4 @@
-.TH SG_LOGS "8" "August 2021" "sg3_utils\-1.47" SG3_UTILS
+.TH SG_LOGS "8" "December 2021" "sg3_utils\-1.48" SG3_UTILS
 .SH NAME
 sg_logs \- access log pages with SCSI LOG SENSE command
 .SH SYNOPSIS
@@ -54,6 +54,10 @@ SENSE command. The third form shows the options that can be used to send a
 LOG SELECT command. The fourth form groups various management options.
 The last form shows the older, deprecated command line interface which is
 maintained for backward compatibility.
+.PP
+When no options are given, just a \fIDEVICE\fR, that is equivalent to calling
+this utility with the \fI\-\-list\fR option. In that case the names of the
+supported log pages (and not any subpages) are listed out.
 .SH OPTIONS
 Arguments to long options are mandatory for short options as well.
 The options are arranged in alphabetical order based on the long
@@ -159,14 +163,13 @@ is ignored. If the \fI\-\-raw\fR option is also given then \fIFN\fR is
 treated as binary.
 .TP
 \fB\-l\fR, \fB\-\-list\fR
-lists the names of all logs sense pages supported by this device. This is
-done by reading the "supported log pages" log page. When used
-twice (e.g. '\-ll') lists the names of all logs sense pages and subpages
-supported by this device, excluding pages whose subpage number is
-0xff (apart from page 0x0,0xff). When used three times then all supported
-pages and subpages reported by the device are list. So the page/subpage
-names and not thrie content is shown with this option. There is a list of
-common log page codes below.
+lists the names of the logs sense pages supported by this device. This is
+done by reading the "supported log pages" log page. When used once only
+log pages, but not subpages, are listed. When used two or more
+times (e.g. '\-ll') lists the names of all logs sense pages and subpages
+supported by this device, including pages whose subpage number is
+0xff. So the page/subpage names but not their contents is shown with this
+option.
 .TP
 \fB\-m\fR, \fB\-\-maxlen\fR=\fILEN\fR
 sets the "allocation length" field in the LOG SENSE cdb. The is the maximum
@@ -222,7 +225,8 @@ should be selected. The default value is 0.
 .TP
 \fB\-q\fR, \fB\-\-pcb\fR
 show Parameter Control Byte settings (only relevant when log parameters
-being output in ASCII).
+being output in ASCII). This byte includes the DU and TSD bits plus
+the 'Format and linking' field (2 bits wide).
 .TP
 \fB\-Q\fR, \fB\-\-ppc\fR
 sets the Parameter Pointer Control (PPC) bit in the LOG SENSE cdb. Default
diff --git a/sg3_utils.spec b/sg3_utils.spec
index dc2bdde2..e219571d 100644
--- a/sg3_utils.spec
+++ b/sg3_utils.spec
@@ -84,7 +84,7 @@ fi
 %{_libdir}/*.la
 
 %changelog
-* Fri Dec 03 2021 - dgilbert at interlog dot com
+* Wed Dec 22 2021 - dgilbert at interlog dot com
 - track t10 changes
   * sg3_utils-1.48
 
diff --git a/src/sg_logs.c b/src/sg_logs.c
index 99fd44aa..ff1797a3 100644
--- a/src/sg_logs.c
+++ b/src/sg_logs.c
@@ -36,7 +36,7 @@
 #include "sg_unaligned.h"
 #include "sg_pr2serr.h"
 
-static const char * version_str = "1.87 20211030";    /* spc6r06 + sbc5r01 */
+static const char * version_str = "1.88 20211222";    /* spc6r06 + sbc5r01 */
 
 #define MX_ALLOC_LEN (0xfffc)
 #define SHORT_RESP_LEN 128
@@ -1502,7 +1502,7 @@ get_pcb_str(int pcb, char * outp, int maxoutlen)
     return outp;
 }
 
-/* SUPP_PAGES_LPAGE [0x0,0x0] */
+/* SUPP_PAGES_LPAGE [0x0,0x0] <sp> */
 static bool
 show_supported_pgs_page(const uint8_t * resp, int len,
                         const struct opts_t * op)
@@ -1534,8 +1534,8 @@ show_supported_pgs_page(const uint8_t * resp, int len,
     return true;
 }
 
-/* SUPP_PAGES_LPAGE,SUPP_SPGS_SUBPG [0x0,0xff] or all subpages of a given
- * page code: [<pg_code>,0xff] */
+/* SUPP_PAGES_LPAGE,SUPP_SPGS_SUBPG [0x0,0xff] <ssp> or all subpages of a
+ * given page code: [<pg_code>,0xff] where <pg_code> > 0 */
 static bool
 show_supported_pgs_sub_page(const uint8_t * resp, int len,
                             const struct opts_t * op)
@@ -1557,28 +1557,31 @@ show_supported_pgs_sub_page(const uint8_t * resp, int len,
         int pg_code = bp[k];
         int subpg_code = bp[k + 1];
 
-        if ((op->do_list == 2) && (subpg_code == 0xff) && (pg_code > 0))
-            continue;
+        /* formerly ignored [pg, 0xff] when pg > 0, don't know why */
         if (NOT_SPG_SUBPG == subpg_code)
             snprintf(b, sizeof(b) - 1, "    0x%02x        ", pg_code);
         else
             snprintf(b, sizeof(b) - 1, "    0x%02x,0x%02x   ", pg_code,
                      subpg_code);
-        lep = pg_subpg_pdt_search(pg_code, subpg_code, op->dev_pdt, -1);
-        if (lep) {
-            if (op->do_brief > 1)
-                printf("    %s\n", lep->name);
-            else if (op->do_brief)
-                printf("%s%s\n", b, lep->name);
-            else
-                printf("%s%s [%s]\n", b, lep->name, lep->acron);
-        } else
+        if ((pg_code > 0) && (subpg_code == 0xff))
             printf("%s\n", b);
+        else {
+            lep = pg_subpg_pdt_search(pg_code, subpg_code, op->dev_pdt, -1);
+            if (lep) {
+                if (op->do_brief > 1)
+                    printf("    %s\n", lep->name);
+                else if (op->do_brief)
+                    printf("%s%s\n", b, lep->name);
+                else
+                    printf("%s%s [%s]\n", b, lep->name, lep->acron);
+            } else
+                printf("%s\n", b);
+        }
     }
     return true;
 }
 
-/* BUFF_OVER_UNDER_LPAGE [0x1]  introduced: SPC-2 */
+/* BUFF_OVER_UNDER_LPAGE [0x1] <bou>  introduced: SPC-2 */
 static bool
 show_buffer_over_under_run_page(const uint8_t * resp, int len,
                                 const struct opts_t * op)
@@ -1703,7 +1706,7 @@ skip:
 }
 
 /* WRITE_ERR_LPAGE; READ_ERR_LPAGE; READ_REV_ERR_LPAGE; VERIFY_ERR_LPAGE */
-/* [0x2, 0x3, 0x4, 0x5]  introduced: SPC-3 */
+/* [0x2, 0x3, 0x4, 0x5] <we, re, rre, ve>  introduced: SPC-3 */
 static bool
 show_error_counter_page(const uint8_t * resp, int len,
                         const struct opts_t * op)
@@ -1781,7 +1784,7 @@ skip:
     return true;
 }
 
-/* NON_MEDIUM_LPAGE [0x6]  introduced: SPC-2 */
+/* NON_MEDIUM_LPAGE [0x6] <nm>  introduced: SPC-2 */
 static bool
 show_non_medium_error_page(const uint8_t * resp, int len,
                            const struct opts_t * op)
@@ -1832,7 +1835,7 @@ skip:
     return true;
 }
 
-/* PCT_LPAGE [0x1a]  introduced: SPC-4 */
+/* PCT_LPAGE [0x1a] <pct>  introduced: SPC-4 */
 static bool
 show_power_condition_transitions_page(const uint8_t * resp, int len,
                                       const struct opts_t * op)
@@ -1916,7 +1919,7 @@ humidity_str(uint8_t h, bool reporting, char * b, int blen)
     return b;
 }
 
-/* ENV_REPORTING_SUBPG [0xd,0x1]  introduced: SPC-5 (rev 02). "mounted"
+/* ENV_REPORTING_SUBPG [0xd,0x1] <env> introduced: SPC-5 (rev 02). "mounted"
  * changed to "other" in spc5r11 */
 static bool
 show_environmental_reporting_page(const uint8_t * resp, int len,
@@ -1998,7 +2001,6 @@ show_environmental_reporting_page(const uint8_t * resp, int len,
             }
         } else
             printf("  <<unexpected parameter code 0x%x\n", pc);
-        printf("\n");
         if (op->do_pcb)
             printf("        <%s>\n", get_pcb_str(bp[2], str, sizeof(str)));
         if (op->filter_given)
@@ -2010,7 +2012,7 @@ skip:
     return true;
 }
 
-/* ENV_LIMITS_SUBPG [0xd,0x2]  introduced: SPC-5 (rev 02) */
+/* ENV_LIMITS_SUBPG [0xd,0x2] <enl> introduced: SPC-5 (rev 02) */
 static bool
 show_environmental_limits_page(const uint8_t * resp, int len,
                                const struct opts_t * op)
@@ -2080,7 +2082,6 @@ show_environmental_limits_page(const uint8_t * resp, int len,
                    humidity_str(bp[11], false, b, blen));
         } else
             printf("  <<unexpected parameter code 0x%x\n", pc);
-        printf("\n");
         if (op->do_pcb)
             printf("        <%s>\n", get_pcb_str(bp[2], str, sizeof(str)));
         if (op->filter_given)
@@ -2092,7 +2093,7 @@ skip:
     return true;
 }
 
-/* CMD_DUR_LIMITS_SUBPG [0x19,0x21]  introduced: SPC-6 (rev 01) */
+/* CMD_DUR_LIMITS_SUBPG [0x19,0x21] <cdl>  introduced: SPC-6 (rev 01) */
 static bool
 show_cmd_dur_limits_page(const uint8_t * resp, int len,
                          const struct opts_t * op)
@@ -2447,7 +2448,7 @@ show_tape_capacity_page(const uint8_t * resp, int len,
 }
 
 /* Data compression: originally vendor specific 0x32 (LTO-5), then
- * ssc-4 standardizes it at 0x1b */
+ * ssc-4 standardizes it at 0x1b <dc> */
 static bool
 show_data_compression_page(const uint8_t * resp, int len,
                            const struct opts_t * op)
@@ -2548,7 +2549,7 @@ skip_para:
     return true;
 }
 
-/* LAST_N_ERR_LPAGE [0x7]  introduced: SPC-2 */
+/* LAST_N_ERR_LPAGE [0x7] <lne>  introduced: SPC-2 */
 static bool
 show_last_n_error_page(const uint8_t * resp, int len,
                        const struct opts_t * op)
@@ -2605,7 +2606,7 @@ show_last_n_error_page(const uint8_t * resp, int len,
     return true;
 }
 
-/* LAST_N_DEFERRED_LPAGE [0xb]  introduced: SPC-2 */
+/* LAST_N_DEFERRED_LPAGE [0xb] <lnd>  introduced: SPC-2 */
 static bool
 show_last_n_deferred_error_page(const uint8_t * resp, int len,
                                 const struct opts_t * op)
@@ -2652,7 +2653,7 @@ show_last_n_deferred_error_page(const uint8_t * resp, int len,
     return true;
 }
 
-/* LAST_N_INQUIRY_DATA_CH_SUBPG [0xb,0x1]  introduced: SPC-5 (rev 17) */
+/* LAST_N_INQUIRY_DATA_CH_SUBPG [0xb,0x1] <lnic> introduced: SPC-5 (rev 17) */
 static bool
 show_last_n_inq_data_ch_page(const uint8_t * resp, int len,
                              const struct opts_t * op)
@@ -2712,7 +2713,7 @@ skip:
     return true;
 }
 
-/* LAST_N_MODE_PG_DATA_CH_SUBPG [0xb,0x2]  introduced: SPC-5 (rev 17) */
+/* LAST_N_MODE_PG_DATA_CH_SUBPG [0xb,0x2] <lnmc> introduced: SPC-5 (rev 17) */
 static bool
 show_last_n_mode_pg_data_ch_page(const uint8_t * resp, int len,
                                  const struct opts_t * op)
@@ -2790,7 +2791,7 @@ static const char * self_test_result[] = {
     "reserved",
     "self test in progress"};
 
-/* SELF_TEST_LPAGE [0x10]  introduced: SPC-3 */
+/* SELF_TEST_LPAGE [0x10] <str>  introduced: SPC-3 */
 static bool
 show_self_test_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -2859,7 +2860,7 @@ show_self_test_page(const uint8_t * resp, int len, const struct opts_t * op)
     return true;
 }
 
-/* TEMPERATURE_LPAGE [0xd]  introduced: SPC-3 */
+/* TEMPERATURE_LPAGE [0xd] <temp>  introduced: SPC-3 */
 static bool
 show_temperature_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -2933,7 +2934,7 @@ show_temperature_page(const uint8_t * resp, int len, const struct opts_t * op)
     return true;
 }
 
-/* START_STOP_LPAGE [0xe]  introduced: SPC-3 */
+/* START_STOP_LPAGE [0xe] <sscc>  introduced: SPC-3 */
 static bool
 show_start_stop_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -3043,7 +3044,7 @@ show_start_stop_page(const uint8_t * resp, int len, const struct opts_t * op)
     return true;
 }
 
-/* APP_CLIENT_LPAGE [0xf]  introduced: SPC-3 */
+/* APP_CLIENT_LPAGE [0xf] <ac>  introduced: SPC-3 */
 static bool
 show_app_client_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -3097,7 +3098,7 @@ show_app_client_page(const uint8_t * resp, int len, const struct opts_t * op)
     return true;
 }
 
-/* IE_LPAGE [0x2f] "Informational Exceptions"  introduced: SPC-3 */
+/* IE_LPAGE [0x2f] <ie> "Informational Exceptions"  introduced: SPC-3 */
 static bool
 show_ie_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -3646,7 +3647,7 @@ show_sas_port_param(const uint8_t * bp, int param_len,
     }
 }
 
-/* PROTO_SPECIFIC_LPAGE [0x18] */
+/* PROTO_SPECIFIC_LPAGE [0x18] <psp> */
 static bool
 show_protocol_specific_page(const uint8_t * resp, int len,
                             const struct opts_t * op)
@@ -3694,7 +3695,7 @@ skip:
 }
 
 /* Returns true if processed page, false otherwise */
-/* STATS_LPAGE [0x19], subpages: 0x0 to 0x1f  introduced: SPC-4 */
+/* STATS_LPAGE [0x19], subpages: 0x0 to 0x1f <gsp,grsp>  introduced: SPC-4 */
 static bool
 show_stats_perform_pages(const uint8_t * resp, int len,
                          const struct opts_t * op)
@@ -3981,7 +3982,7 @@ show_stats_perform_pages(const uint8_t * resp, int len,
 }
 
 /* Returns true if processed page, false otherwise */
-/* STATS_LPAGE [0x19], CACHE_STATS_SUBPG [0x20]  introduced: SPC-4 */
+/* STATS_LPAGE [0x19], CACHE_STATS_SUBPG [0x20] <cms>  introduced: SPC-4 */
 static bool
 show_cache_stats_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -4114,7 +4115,7 @@ show_cache_stats_page(const uint8_t * resp, int len, const struct opts_t * op)
     return true;
 }
 
-/* FORMAT_STATUS_LPAGE [0x8]  introduced: SBC-2 */
+/* FORMAT_STATUS_LPAGE [0x8] <fs>  introduced: SBC-2 */
 static bool
 show_format_status_page(const uint8_t * resp, int len,
                         const struct opts_t * op)
@@ -4202,7 +4203,7 @@ skip:
     return true;
 }
 
-/* Non-volatile cache page [0x17]  introduced: SBC-2 */
+/* Non-volatile cache page [0x17] <nvc>  introduced: SBC-2 */
 static bool
 show_non_volatile_cache_page(const uint8_t * resp, int len,
                              const struct opts_t * op)
@@ -4288,7 +4289,7 @@ skip:
     return true;
 }
 
-/* LB_PROV_LPAGE [0xc]  introduced: SBC-3 */
+/* LB_PROV_LPAGE [0xc] <lbp> introduced: SBC-3 */
 static bool
 show_lb_provisioning_page(const uint8_t * resp, int len,
                           const struct opts_t * op)
@@ -4381,7 +4382,7 @@ skip:
     return true;
 }
 
-/* UTILIZATION_SUBPG [0xe,0x1]  introduced: SBC-4 */
+/* UTILIZATION_SUBPG [0xe,0x1] <util>  introduced: SBC-4 */
 static bool
 show_utilization_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -4451,7 +4452,7 @@ skip:
     return true;
 }
 
-/* SOLID_STATE_MEDIA_LPAGE [0x11]  introduced: SBC-3 */
+/* SOLID_STATE_MEDIA_LPAGE [0x11] <ssm>  introduced: SBC-3 */
 static bool
 show_solid_state_media_page(const uint8_t * resp, int len,
                             const struct opts_t * op)
@@ -4528,7 +4529,7 @@ static const char * dt_dev_activity[] = {
     "Diagnostic operation in progress", /* 10 */
 };
 
-/* DT device status [0x11] (ssc, adc) */
+/* DT device status [0x11] <dtds> (ssc, adc) */
 static bool
 show_dt_device_status_page(const uint8_t * resp, int len,
                            const struct opts_t * op)
@@ -4666,7 +4667,7 @@ skip:
     return true;
 }
 
-/* TapeAlert response [0x12] (adc,ssc) */
+/* TapeAlert response [0x12] <tar> (adc,ssc) */
 static bool
 show_tapealert_response_page(const uint8_t * resp, int len,
                              const struct opts_t * op)
@@ -4755,7 +4756,7 @@ static const char * req_rec_arr[NUM_REQ_REC_ARR_ELEMS] = {
         "re-insert volume",     /* 0xf */
 };
 
-/* Requested recovery [0x13] (ssc) */
+/* REQ_RECOVERY_LPAGE Requested recovery [0x13] <rr> (ssc) */
 static bool
 show_requested_recovery_page(const uint8_t * resp, int len,
                              const struct opts_t * op)
@@ -4816,7 +4817,7 @@ skip:
     return true;
 }
 
-/* SAT_ATA_RESULTS_LPAGE (SAT-2) [0x16] */
+/* SAT_ATA_RESULTS_LPAGE (SAT-2) [0x16] <aptr> */
 static bool
 show_ata_pt_results_page(const uint8_t * resp, int len,
                          const struct opts_t * op)
@@ -4906,7 +4907,7 @@ static const char * reassign_status[] = {
     "Logical block unsuccessfully reassigned by application client", /* 8 */
 };
 
-/* Background scan results [0x15,0] for disk  introduced: SBC-3 */
+/* Background scan results [0x15,0] <bsr> for disk  introduced: SBC-3 */
 static bool
 show_background_scan_results_page(const uint8_t * resp, int len,
                                   const struct opts_t * op)
@@ -5034,7 +5035,7 @@ skip:
     return true;
 }
 
-/* ZONED_BLOCK_DEV_STATS_SUBPG [0x14,0x1]  introduced: zbc2r01 */
+/* ZONED_BLOCK_DEV_STATS_SUBPG [0x14,0x1] <zbds>  introduced: zbc2r01 */
 static bool
 show_zoned_block_dev_stats(const uint8_t * resp, int len,
                            const struct opts_t * op)
@@ -5234,7 +5235,7 @@ skip:
     return true;
 }
 
-/* PENDING_DEFECTS_SUBPG [0x15,0x1]  introduced: SBC-4 */
+/* PENDING_DEFECTS_SUBPG [0x15,0x1] <pd>  introduced: SBC-4 */
 static bool
 show_pending_defects_page(const uint8_t * resp, int len,
                           const struct opts_t * op)
@@ -5310,7 +5311,7 @@ skip:
     return true;
 }
 
-/* BACKGROUND_OP_SUBPG [0x15,0x2]  introduced: SBC-4 rev 7 */
+/* BACKGROUND_OP_SUBPG [0x15,0x2] <bop>  introduced: SBC-4 rev 7 */
 static bool
 show_background_op_page(const uint8_t * resp, int len,
                         const struct opts_t * op)
@@ -5367,7 +5368,7 @@ skip:
     return true;
 }
 
-/* LPS misalignment page [0x15,0x3]  introduced: SBC-4 rev 10
+/* LPS misalignment page [0x15,0x3] <lps>  introduced: SBC-4 rev 10
    LPS: "Long Physical Sector" a term from an ATA feature set */
 static bool
 show_lps_misalignment_page(const uint8_t * resp, int len,
@@ -5430,7 +5431,7 @@ skip:
     return true;
 }
 
-/* Service buffer information [0x15] (adc) */
+/* Service buffer information [0x15] <sbi> (adc) */
 static bool
 show_service_buffer_info_page(const uint8_t * resp, int len,
                               const struct opts_t * op)
@@ -5485,7 +5486,7 @@ skip:
     return true;
 }
 
-/* Sequential access device page [0xc] for tape */
+/* Sequential access device page [0xc] <sad> for tape */
 static bool
 show_sequential_access_page(const uint8_t * resp, int len,
                             const struct opts_t * op)
@@ -5599,7 +5600,7 @@ skip:
     return true;
 }
 
-/* 0x14 for tape and ADC */
+/* Device statistics 0x14 <ds> for tape and ADC */
 static bool
 show_device_stats_page(const uint8_t * resp, int len,
                        const struct opts_t * op)
@@ -5778,7 +5779,7 @@ skip:
     return true;
 }
 
-/* 0x14 for media changer */
+/* Media changer statistics 0x14 <mcs> for media changer */
 static bool
 show_media_stats_page(const uint8_t * resp, int len, const struct opts_t * op)
 {
@@ -5913,7 +5914,7 @@ skip:
     return true;
 }
 
-/* Element statistics page, 0x15 for SMC */
+/* Element statistics page, 0x15 <els> for SMC */
 static bool
 show_element_stats_page(const uint8_t * resp, int len,
                         const struct opts_t * op)
@@ -5965,7 +5966,7 @@ skip:
     return true;
 }
 
-/* 0x16 for tape */
+/* Tape diagnostic data [0x16] <tdd> for tape */
 static bool
 show_tape_diag_data_page(const uint8_t * resp, int len,
                          const struct opts_t * op)
@@ -6051,7 +6052,7 @@ skip:
     return true;
 }
 
-/* 0x16 for media changer */
+/* Media changer diagnostic data [0x16] <mcdd> for media changer */
 static bool
 show_mchanger_diag_data_page(const uint8_t * resp, int len,
                              const struct opts_t * op)
@@ -6214,7 +6215,7 @@ volume_stats_history(const uint8_t * xp, int len)
     }
 }
 
-/* Volume Statistics log page and subpages (ssc-4) [0x17, 0x0-0xf] */
+/* Volume Statistics log page and subpages (ssc-4) [0x17, 0x0-0xf] <vs> */
 static bool
 show_volume_stats_pages(const uint8_t * resp, int len,
                        const struct opts_t * op)
@@ -6513,7 +6514,7 @@ static const char * tape_alert_strs[] = {
     "WORM medium - overwrite attempted",
 };
 
-/* TAPE_ALERT_LPAGE [0x2e] */
+/* TAPE_ALERT_LPAGE [0x2e] <ta> */
 static bool
 show_tape_alert_ssc_page(const uint8_t * resp, int len,
                          const struct opts_t * op)
@@ -6571,8 +6572,14 @@ show_seagate_cache_page(const uint8_t * resp, int len,
     const uint8_t * bp;
     char str[PCB_STR_LEN];
 
-    if (op->verbose || ((! op->do_raw) && (0 == op->do_hex)))
-        printf("Seagate cache page [0x37]\n");
+    if (op->verbose || ((! op->do_raw) && (0 == op->do_hex))) {
+        if (resp[1] > 0) {
+            printf("Suspicious page 0x37, SPF=0 but subpage=0x%x\n", resp[1]);
+            if (op->verbose)
+                printf("... try vendor=wdc\n");
+        } else
+            printf("Seagate cache page [0x37]\n");
+    }
     num = len - 4;
     bp = &resp[0] + 4;
     while (num > 3) {
@@ -6772,7 +6779,7 @@ decode_page_contents(const uint8_t * resp, int len, struct opts_t * op)
     if (lep && lep->show_pagep)
         done = (*lep->show_pagep)(resp, len, op);
 
- if (! done) {
+    if (! done) {
         if (subpg_code > 0)
             printf("Unable to decode page = 0x%x, subpage = 0x%x, here is "
                    "hex:\n", pg_code, subpg_code);
diff --git a/src/sg_opcodes.c b/src/sg_opcodes.c
index 9d908248..54b90723 100644
--- a/src/sg_opcodes.c
+++ b/src/sg_opcodes.c
@@ -33,7 +33,7 @@
 
 #include "sg_pt.h"
 
-static const char * version_str = "0.72 20211114";    /* spc6r05 */
+static const char * version_str = "0.72 20211221";    /* spc6r05 */
 
 
 #define SENSE_BUFF_LEN 64       /* Arbitrary, could be larger */
@@ -51,6 +51,7 @@ static const char * version_str = "0.72 20211114";    /* spc6r05 */
 #define SEAGATE_READ_UDS_DATA_CMD 0xf7  /* may start reporting vendor cmds */
 
 static int peri_dtype = -1; /* ugly but not easy to pass to alpha compare */
+static bool no_final_msg = false;
 
 static struct option long_options[] = {
         {"alpha", no_argument, 0, 'a'},
@@ -1075,20 +1076,33 @@ main(int argc, char * argv[])
     if (NULL == rsoc_buff) {
         pr2serr("Unable to allocate memory\n");
         res = sg_convert_errno(ENOMEM);
+        no_final_msg = true;
         goto err_out;
     }
 
     if (op->opcode < 0) {
         /* Try to open read-only */
         if ((sg_fd = scsi_pt_open_device(op->device_name, true, vb)) < 0) {
-            pr2serr("sg_opcodes: error opening file (ro): %s: %s\n",
-                    op->device_name, safe_strerror(-sg_fd));
+            int err = -sg_fd;
+
+            if (op->verbose)
+                pr2serr("sg_opcodes: error opening file (ro): %s: %s\n",
+                        op->device_name, safe_strerror(err));
+#ifndef SG_LIB_WIN32
+            if (ENOENT == err) {
+                /* file or directory in the file's path doesn't exist, no
+                 * point in retrying with read-write flag */
+                res = sg_convert_errno(err);
+                goto err_out;
+            }
+#endif
             goto open_rw;
         }
         ptvp = construct_scsi_pt_obj_with_fd(sg_fd, op->verbose);
         if (NULL == ptvp) {
             pr2serr("Out of memory (ro)\n");
             res = sg_convert_errno(ENOMEM);
+            no_final_msg = true;
             goto err_out;
         }
         if (op->no_inquiry && (peri_dtype < 0))
@@ -1110,6 +1124,7 @@ main(int argc, char * argv[])
             pr2serr("sg_opcodes: %s doesn't respond to a SCSI INQUIRY\n",
                     op->device_name);
             res = SG_LIB_CAT_OTHER;
+            no_final_msg = true;
             goto err_out;
         }
     }
@@ -1121,12 +1136,14 @@ open_rw:                /* if not already open */
             pr2serr("sg_opcodes: error opening file (rw): %s: %s\n",
                     op->device_name, safe_strerror(-sg_fd));
             res = sg_convert_errno(-sg_fd);
+            no_final_msg = true;
             goto err_out;
         }
         ptvp = construct_scsi_pt_obj_with_fd(sg_fd, op->verbose);
         if (NULL == ptvp) {
             pr2serr("Out of memory (rw)\n");
             res = sg_convert_errno(ENOMEM);
+            no_final_msg = true;
             goto err_out;
         }
     }
@@ -1144,6 +1161,7 @@ open_rw:                /* if not already open */
     if (res) {
         sg_get_category_sense_str(res, sizeof(b), b, vb);
         pr2serr("%s: %s\n", op_name, b);
+        no_final_msg = true;
         if ((0 == op->servact) && (op->opcode >= 0))
             pr2serr("    >> perhaps try again without a service action "
                     "[SA] of 0\n");
@@ -1153,12 +1171,12 @@ open_rw:                /* if not already open */
     if (op->do_taskman) {
         if (op->do_raw) {
             dStrRaw((const char *)rsoc_buff, act_len);
-            goto err_out;
+            goto fini;
         }
         printf("\nTask Management Functions supported by device:\n");
         if (op->do_hex) {
             hex2stdout(rsoc_buff, act_len, 1);
-            goto err_out;
+            goto fini;
         }
         if (rsoc_buff[0] & 0x80)
             printf("    Abort task\n");
@@ -1187,6 +1205,7 @@ open_rw:                /* if not already open */
                 pr2serr("when REPD given, byte 3 of response should be >= "
                         "12\n");
                 res = SG_LIB_CAT_OTHER;
+                no_final_msg = true;
                 goto err_out;
             } else
                 printf("  Extended parameter data:\n");
@@ -1210,11 +1229,11 @@ open_rw:                /* if not already open */
         len = (len < act_len) ? len : act_len;
         if (op->do_raw) {
             dStrRaw((const char *)rsoc_buff, len);
-            goto err_out;
+            goto fini;
         }
         if (op->do_hex) {
             hex2stdout(rsoc_buff, len, 1);
-            goto err_out;
+            goto fini;
         }
         list_all_codes(rsoc_buff, len, op, ptvp);
     } else {    /* asked about specific command */
@@ -1224,11 +1243,11 @@ open_rw:                /* if not already open */
         cd_len = (cd_len < act_len) ? cd_len : act_len;
         if (op->do_raw) {
             dStrRaw((const char *)rsoc_buff, len);
-            goto err_out;
+            goto fini;
         }
         if (op->do_hex) {
             hex2stdout(rsoc_buff, len, 1);
-            goto err_out;
+            goto fini;
         }
         list_one(rsoc_buff, cd_len, rep_opts, op);
     }
@@ -1242,5 +1261,10 @@ err_out:
         destruct_scsi_pt_obj(ptvp);
     if (sg_fd >= 0)
         scsi_pt_close_device(sg_fd);
-    return res;
+    if ((0 == op->verbose) && (! no_final_msg)) {
+        if (! sg_if_can2stderr("sg_opcodes failed: ", res))
+            pr2serr("Some error occurred, try again with '-v' "
+                    "or '-vv' for more information\n");
+    }
+    return (res >= 0) ? res : SG_LIB_CAT_OTHER;
 }