Kozmotronik Q&A - Recent questions

Convert date string to unix time in C

Mon, 27 Oct 2025 12:58:18 +0000

I need to convert a formatted date string to Unix time (time_t) in ESP-IDF.

I need to obtain the production (compilation) date using the esp_app_get_description() function, which returns an esp_app_desc_t structure containing application-specific information. This contains time and date fields from which I can obtain the production date string.

The formatted date and time are stored separately in the date and time fields, respectively, and have the following format:

17:25:41
Oct 24, 2025

I know that I need to merge those fields first, but I don't know how to convert this date string to time_t.

rst:0x8 (TG1WDT_SYS_RST),boot:0xc (SPI_FAST_FLASH_BOOT)

Fri, 29 Aug 2025 14:23:10 +0000

I'm getting this error when I monitor the app I flashed to ESP32-C3-DevKitM-1. Here is the complete log:

--- esp-idf-monitor 1.5.0 on /dev/ttyACM0 115200
--- Quit: Ctrl+] | Menu: Ctrl+T | Help: Ctrl+T followed by Ctrl+H
I (99) esp_image: segment 2: paddr=0002b840 vaddr=40380000 size=ESP-ROM:esp32c3-api1-20210207
Build:Feb  7 2021
rst:0x15 (USB_UART_CHIP_RESET),boot:0xc (SPI_FAST_FLASH_BOOT)
Saved PC:0x400462e0
--- 0x400462e0: ets_delay_us in ROM

SPIWP:0xee
mode:DIO, clock div:1
load:0x3fcd5820,len:0x1574
load:0x403cc710,len:0xc34
load:0x403ce710,len:0x2f64
entry 0x403cc71a
I (24) boot: ESP-IDF v5.4.2-dirty 2nd stage bootloader
I (24) boot: compile time Aug 29 2025 15:08:51
I (25) boot: chip revision: v0.3
I (25) boot: efuse block revision: v1.1
I (29) boot.esp32c3: SPI Speed      : 80MHz
I (32) boot.esp32c3: SPI Mode       : DIO
I (37) boot.esp32c3: SPI Flash Size : 2MB
I (40) boot: Enabling RNG early entropy source...
I (44) boot: Partition Table:
I (47) boot: ## Label            Usage          Type ST Offset   Length
I (53) boot:  0 nvs              WiFi data        01 02 0000a000 00006000
I (60) boot:  1 phy_init         RF data          01 01 00010000 00001000
I (66) boot:  2 factory          factory app      00 00 00020000 00100000
I (73) boot:  3 app_data         WiFi data        01 02 00120000 00002000
I (79) boot: End of partition table
I (83) esp_image: segment 0: paddr=00020020 vaddr=3c020020 size=09d64h ( 40292) map
I (97) esp_image: segment 1: paddr=00029d8c vaddr=3fc8c400 size=01aach (  6828) load
I (99) esp_image: segment 2: paddr=0002b840 vaddr=40380000 size=047d8h ( 18392) load
I (108) esp_image: segment 3: paddr=00030020 vaddr=42000020 size=1fd20h (130336) map
I (133) esp_image: segment 4: paddr=0004fd48 vaddr=403847d8 size=07a40h ( 31296) load
I (139) esp_image: segment 5: paddr=00057790 vaddr=50000000 size=0001ch (    28) load
I (143) boot: Loaded app from partition at offset 0x20000
I (144) boot: Disabling RNG early entropy source...
I (358) cpu_start: Unicore app
I (366) cpu_start: Pro cpu start user code
I (366) cpu_start: cpu freq: 160000000 Hz
I (367) app_init: Application information:
I (367) app_init: Project name:     relay_chn_test
I (371) app_init: App version:      0.5.0-47-gdea9f1e-dirty
I (376) app_init: Compile time:     Aug 29 2025 15:08:41
I (381) app_init: ELF file SHA256:  869ab1a0e...
I (386) app_init: ESP-IDF:          v5.4.2-dirty
I (390) efuse_init: Min chip rev:     v0.3
I (394) efuse_init: Max chip rev:     v1.99 
I (398) efuse_init: Chip rev:         v0.3
I (402) heap_init: Initializing. RAM available for dynamic allocation:
I (408) heap_init: At 3FC8F260 len 00030DA0 (195 KiB): RAM
I (413) heap_init: At 3FCC0000 len 0001C710 (113 KiB): Retention RAM
I (419) heap_init: At 3FCDC710 len 00002950 (10 KiB): Retention RAM
I (425) heap_init: At 5000001C len 00001FCC (7 KiB): RTCRAM
I (431) spi_flash: detected chip: generic
I (434) spi_flash: flash io: dio
W (437) spi_flash: Detected size(4096k) larger than the size in the binary image header(2048k). Using the size in the binary image header.
I (450) sleep_gpio: Configure to isolate all GPIO pins in sleep state
I (456) sleep_gpio: Enable automatic switching of GPIO sleep configuration
I (462) main_task: Started on CPU0
I (462) main_task: Calling app_main()
I (502) RELAY_CHN_TEST: test_nvs_flash_init: NVS flash init partition return: ESP_OK
I (512) gpio: GPIO[0]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (512) gpio: GPIO[1]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (522) gpio: GPIO[2]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (522) gpio: GPIO[3]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (532) gpio: GPIO[4]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (542) gpio: GPIO[5]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (552) gpio: GPIO[6]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (562) gpio: GPIO[7]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (562) gpio: GPIO[8]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (572) gpio: GPIO[9]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (582) gpio: GPIO[10]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (592) gpio: GPIO[11]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (602) gpio: GPIO[12]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (612) gpio: GPIO[13]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (612) gpio: GPIO[14]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
I (622) gpio: GPIO[15]| InputEn: 0| OutputEn: 0| OpenDrain: 0| Pullup: 1| Pulldown: 0| Intr:0 
ESP-ROM:esp32c3-api1-20210207
Build:Feb  7 2021
rst:0x8 (TG1WDT_SYS_RST),boot:0xc (SPI_FAST_FLASH_BOOT)
Saved PC:0x40380102
--- 0x40380102: _panic_handler at /disk/Depo/Developer/SDK/esp-idf/v5.4.2/esp-idf/components/riscv/vectors.S:141

SPIWP:0xee
mode:DIO, clock div:1
load:0x3fcd5820,len:0x1574
load:0x403cc710,len:0xc34
load:0x403ce710,len:0x2f64
entry 0x403cc71a

From there on the device resets over and over again with the same error.

Replace lines that have RELAY_CHN_STATE_* pattern in vscode

Tue, 26 Aug 2025 12:13:01 +0000

In vscode, I'd like to replace following text which occurs in multiple lines with different enum parameters:

TEST_ASSERT_EQUAL(RELAY_CHN_STATE_*, relay_chn_get_state(ch));

with:

check_all_channels_for_state(RELAY_CHN_STATE_*);

Where RELAY_CHN_STATE_* is an enum value that may have variety of states.

Replace a line with regex until the next non-blank line in VS Code

Tue, 12 Aug 2025 08:10:45 +0000

What I want to do is to replace a non-blank line plus some spaces that extends until the next non-blank line. In particular here is a sample piece of text that shows the structure I want to replace:

TEST_CASE("Tilt Reverse to Run Reverse transition with inertia", "[relay_chn][tilt][inertia]")
{
    uint8_t ch = 0;

    TEST_ESP_OK(relay_chn_create(gpio_map, gpio_count));
    ...
}

I want to remove the uint8_t ch = 0; and all the spaces until the TEST* line. SO the end result should look like this:

TEST_CASE("Tilt Reverse to Run Reverse transition with inertia", "[relay_chn][tilt][inertia]")
{
    TEST_ESP_OK(relay_chn_create(gpio_map, gpio_count));
    ...
}

Passing a pointer as event_data parameter in ESP-IDF

Mon, 11 Aug 2025 12:56:35 +0000

I need to pass a pointer to a special type of structure as event_data parameter in ESP-IDF. However, as per the `event_loop documentation:

Posts an event to the specified event loop. The event loop library
keeps a copy of event_data and manages the copy’s lifetime
automatically (allocation + deletion); this ensures that the data the
handler recieves is always valid.

Currently I pass the pointer as usual like following:

esp_event_post_to(relay_chn_event_loop,
                      RELAY_CHN_CMD_EVENT,
                      cmd,
                      chn_ctl,
                      sizeof(relay_chn_ctl_t*),
                      portMAX_DELAY);

Then I receive it in the handler like following:

static void relay_chn_event_handler(void* handler_arg, esp_event_base_t event_base, int32_t event_id, void* event_data)
{
    relay_chn_ctl_t* chn_ctl = (relay_chn_ctl_t*) event_data;
    ...
}

But this way, the memory addres isn't passed as expected and the chn_ctl in the handler has a different memory address. Eventually I get the following error that indicates a system crash for a NULL pointer right after the esp_event_post_to is executed:

Guru Meditation Error: Core 0 panic'ed (LoadProhibited). Exception
was unhandled.

What is the proper way to pass a pointer through the event_data parameter?

Bootloader size error when I set log level to DEBUG in ESP-IDF

Mon, 11 Aug 2025 10:22:58 +0000

I've got the following error when I set the log level to Debug:

Error: Bootloader binary size 0x72c0 bytes is too large for partition
table offset 0x8000. Bootloader binary can be maximum 0x7000 (28672)
bytes unless the partition table offset is increased in the Partition
Table section of the project configuration menu

Any ideas how to solve this?

How to remove a line completely using regex in VS Code

Fri, 08 Aug 2025 07:35:24 +0000

I need to use regex to find and replace in VS Code. What I want to do is delete the following line completely. But I also want to remove the space left by the deleted line. In other words, the deleted line should not be followed by a new line (\n).

 * @param chn_id The ID of the relay channel whose state is to be retrieved.

Schematic sheet template not updated in KiCad

Fri, 25 Jul 2025 11:31:19 +0000

I made some changes to a schematic sheet template file that I had been created and added to a schematic before. But the changes aren't applied to the schematic file. What should I do so the changes are applied to the file?

My KiCad version is v9.0.3.

Steam folder is not executable error

Thu, 24 Jul 2025 21:06:23 +0000

I want to add extra drive to my steam from Settings > Storage. But it does not allow me to select a folder from the other mounted disk giving the error: Steam folder is not executable. What is the problem with the disk?

This is the /etc/fstab entry of the mounted disk:

UUID=DISKUUID   MOUNTPATH    ext4         nofail,users                           0 0

What is the proper way to rename a KiCad project

Thu, 24 Jul 2025 15:27:39 +0000

I have a KiCad project that I've been working on. But now, the project name had to be changed, so I have to rename the project.

How do I rename it properly so the all KiCad files get updated with the new name?

How to run an app with a different locale in Linux

Thu, 24 Jul 2025 13:36:48 +0000

Let's say I want to run Visual Studio Code with English (en_US.UTF-8) or default Linux (C) locale. Is this possible?

How to exit qemu in an ESP-IDF?

Thu, 24 Jul 2025 11:54:53 +0000

I started the qemu using idf.py qemu monitor command. I tried to terminate it with CTRL+C to interrupt the process but it didn't worked. What is the proper way to exit qemu in ESP-IDF?

How to enable GCOV coverage in ESP-IDF

Thu, 24 Jul 2025 09:35:45 +0000

I want to enable the GCOV code coverage for my unit tests. I work in VSCode IDE and I am following their instructions to get the coverage working. But the ESP-IDF does not recognize the app_trace configuration parameters somehow and if I build the test project, I get the following errors:

Loading defaults file /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults...
/disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults:5 CONFIG_ESP_TASK_WDT was replaced with CONFIG_ESP_TASK_WDT_INIT
warning: unknown kconfig symbol 'APPTRACE_DEST_UART' assigned to 'y' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults
warning: unknown kconfig symbol 'APPTRACE_DEST_NONE' assigned to 'n' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults
warning: unknown kconfig symbol 'APPTRACE_ENABLE' assigned to 'y' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults
warning: unknown kconfig symbol 'APPTRACE_LOCK_ENABLE' assigned to 'y' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults
warning: unknown kconfig symbol 'APPTRACE_ONPANIC_HOST_FLUSH_TMO' assigned to '-1' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults
warning: unknown kconfig symbol 'APPTRACE_POSTMORTEM_FLUSH_THRESH' assigned to '0' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults
warning: unknown kconfig symbol 'APPTRACE_PENDING_DATA_SIZE_MAX' assigned to '0' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults
warning: unknown kconfig symbol 'APPTRACE_GCOV_ENABLE' assigned to 'y' in /disk/Projeler/ESP-Components/relay_chn/test_apps/sdkconfig.defaults

Here is my sdkconfig.defults file

# Disable task WDT for tests
CONFIG_ESP_TASK_WDT_INIT=n

# Relay Channel Driver Default Configuration for Testing
# Keep this as short as possible for tests
CONFIG_RELAY_CHN_OPPOSITE_INERTIA_MS=200
CONFIG_RELAY_CHN_COUNT=2
CONFIG_RELAY_CHN_ENABLE_TILTING=y

# App Trace config
CONFIG_APPTRACE_DEST_JTAG=y
CONFIG_APPTRACE_ENABLE=y
CONFIG_APPTRACE_LOCK_ENABLE=y
CONFIG_APPTRACE_ONPANIC_HOST_FLUSH_TMO=-1
CONFIG_APPTRACE_POSTMORTEM_FLUSH_THRESH=0
CONFIG_APPTRACE_PENDING_DATA_SIZE_MAX=0
CONFIG_APPTRACE_GCOV_ENABLE=y

And here is my test_apps/main/CMakeLists.txt

# === These files must be included in any case ===
set(srcs "test_common.c"
         "test_app_main.c"
         "test_relay_chn_core.c"
         "test_relay_chn_listener.c")

if(CONFIG_RELAY_CHN_ENABLE_TILTING)
    list(APPEND srcs "test_relay_chn_tilt.c")
endif()

message(STATUS "srcs=${srcs}")

# In order for the cases defined by `TEST_CASE` to be linked into the final elf,
# the component can be registered as WHOLE_ARCHIVE
idf_component_register(
    SRCS ${srcs}
    INCLUDE_DIRS "."
    REQUIRES unity relay_chn app_trace
    WHOLE_ARCHIVE
)

What am I missing?

How to exit QEMU automatically when target restarts in ESP-IDF

Wed, 23 Jul 2025 20:38:04 +0000

How to exit QEMU programmatically in ESP-IDF when esp_restart executed?

I run local tests in qemu using idf.py qemu command. When qemu finishes running tests, it keeps running. I want it to exit when it finishes the tests. How can I do that?

How to add relative file links in Github or Gitea editor

Tue, 22 Jul 2025 21:58:13 +0000

I want to add internal file links, e.g. to a source code file that belongs to a specific commit or branch in the comment editor. How could I do that?