Kozmotronik Q&A - Recent questions and answers

Answered: Convert date string to unix time in C

Mon, 27 Oct 2025 13:43:05 +0000

You should use the strptime() for this purpose. It converts a string representation of time to a time tm structure. strptime() works as the oppsite of strftime() function. Now let's see how the date obtained from the esp_app_desc_t can be converted to unix time as time_t.

Merge the date and time fields of esp_app_desc_t into a buffer:

 char buf[32];

 const esp_app_desc_t *app_desc = esp_app_get_description();

 // Merge date and time fields
 strncpy(buf, app_desc->date, sizeof(buf));
 strncat(buf, " ", sizeof(buf) - strlen(buf) - 1);
 strncat(buf, app_desc->time, sizeof(buf) - strlen(buf) - 1);

Then convert it to time_t

 time_t prod_time;
 struct tm prod_tm;
 memset(&prod_tm, 0, sizeof(prod_tm));
 strptime(buf, "%b %d %Y %H:%M:%S", &prod_tm);
 prod_time = mktime(&prod_tm);

Here is the full snippet:

#include <time.h>
#include <string.h>
#include "esp_log.h"

void production_time_to_ctime(void)
{
    char buf[32];
    time_t prod_time;

    const esp_app_desc_t *app_desc = esp_app_get_description();

    // Merge date and time fields
    strncpy(buf, app_desc->date, sizeof(buf));
    strncat(buf, " ", sizeof(buf) - strlen(buf) - 1);
    strncat(buf, app_desc->time, sizeof(buf) - strlen(buf) - 1);

    ESP_LOGI(TAG, "production_time_init: merged time string: %s", buf);

    struct tm prod_tm;
    memset(&prod_tm, 0, sizeof(prod_tm));
    strptime(buf, "%b %d %Y %H:%M:%S", &prod_tm);
    prod_time = mktime(&prod_tm);
    ESP_LOGI(TAG, "production_time_init: unix time: %lld", prod_time);
}

References

https://stackoverflow.com/questions/69965179/convert-string-to-time-t-in-c

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

Fri, 29 Aug 2025 14:28:53 +0000

This reset occurs when an unimplemented GPIO pin is accessed. The following pins are absent on ESP32-C3-DevKitM-1 board: 11, 12, 13, 14, 15.

You need to check the board's or module's datasheet to see what GPIO pins are available and update your code accordingly.

Reference
https://esp32.com/viewtopic.php?t=32799

Answered: Replace lines that have RELAY_CHN_STATE_* pattern in vscode

Tue, 26 Aug 2025 12:55:31 +0000

Here is how to do what you want:

Copy and paste the text into the vscode's search bar and enable regex search
Escape the function parantheses: TEST_ASSERT_EQUAL$RELAY_CHN_STATE_FORWARD, relay_chn_get_state\(ch$\);
Capture the enum by enclosing it with paranteses: (RELAY_CHN_STATE_FORWARD)
Modify the enum so that it matches and captures all possible states (e.g. REVERSE, STOPPED etc.): (RELAY_CHN_STATE_[A-Z_]+)
Optionally you can add \s* between two parameters, after the first parameter's comma. This will match the text whether or not it has a space between two parameters.
The final regex statement should be:

TEST_ASSERT_EQUAL((RELAY_CHNSTATE[A-Z_]+),\s* relay_chn_get_state(ch));
Finally paste this with the captured value into the replace box:

check_all_channels_for_state($1);

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

Tue, 12 Aug 2025 08:13:53 +0000

In the search box of VS Code turn on the regex by pressing the .* button. Then past the following expression:

uint8_t ch = 0;\r?[\n]+\t?[\s]+

Leave the Replace box blank and either replace one by one or all at once.

Answered: Passing a pointer as event_data parameter in ESP-IDF

Mon, 11 Aug 2025 13:10:47 +0000

Since the event_loop library makes a copy of the event_data parameter, the original pointer value should be passed by wrapping it by another pointer, instead of passing the original pointer directly.

Here is the fixed version of the code:

esp_event_post_to(relay_chn_event_loop,
                      RELAY_CHN_CMD_EVENT,
                      cmd,
                      &chn_ctl,
                      sizeof(chn_ctl),
                      portMAX_DELAY);

And the handler:

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;
    ...
}

This way, the original pointer value will be preserved by pointing it by another pointer:

wrapper_pointer->original_pointer

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

Mon, 11 Aug 2025 10:26:39 +0000

As the error says, this could be solved by increasing the offset of the partition table. To do this, open the sdkconfig editor either in UI if you use IDE, or by idf.py menuconfig. Then Partition Table > Offset of partition table and increase the offset value as needed. I.e. in your case it can be 0x9000.

Answered: How to remove a line completely using regex in VS Code

Fri, 08 Aug 2025 07:41:11 +0000

What you need to do:
CTRL + SHIFT + F (search entire project) or CTRL + F to search within a file.
Press the .* button to enable regex mode.
Paste the following regex into the Find field:

^[ \t]*\* @param chn_id.*\r?\n

Explanation:

^[ \t]* → spaces (space/tab) at the beginning of the line
\* @param chn_id → line content
.* → capture the rest
\r?\n → delete the end of the line
Leave the Replace field blank (i.e., delete)
Either replace all or replace one by one

Answered: Schematic sheet template not updated in KiCad

Fri, 25 Jul 2025 11:38:30 +0000

In order to apply new changes from the template sheet to the current file, you need to delete the embedded reference. To do that, open the schematic editor and follow:

File > Schematic Settings... > Schematic Data > Embedded Files
There you should see an embedded file reference, select and delete it and then close the window.
Now go to the File > Page Settings.. again
From the Drawing Sheet section select the template file you modified and click OK

Now the changes should be applied to the page.

Answered: Steam folder is not executable error

Thu, 24 Jul 2025 21:14:46 +0000

The problem is with the users fuse flag. Remove that flag and you should be able to choose any folder of that disk.

UUID=DISKUUID   MOUNTPATH    ext4         nofail                           0 0

Source
https://askubuntu.com/a/1324802/1599999

Answered: What is the proper way to rename a KiCad project

Thu, 24 Jul 2025 15:41:09 +0000

In order to change the project name properly and propagate the new name to all project files, we should rename the project from the File menu of KiCad.

Open the main project window by clicking the *`.kicadpro`** (*.pro for KiCad 5.x and earlier_) file
Click File > Save As... and save the project with the new name.

IMPORTANT
This should only be made from the main window so that KiCad update all refences in files.

References

Answered: How to run an app with a different locale in Linux

Thu, 24 Jul 2025 15:07:52 +0000

It is quite possible and fairly simple. We just have to make sure the locale we want to set is already installed on the system.

So, in order to set a specific locale for an app, all we have to do is to edit its launcher via either GUI or CLI or its text file.
The editing via GUI depends on the desktop environment. We should be able to find it in the main launcher settings. That's why I will only share editing the relevant *.desktop file.

The general format to set the locale for an app is:

env LANG=<desired-lang-code> app_name

In this case it is env LANG=en_US.UTF-8 for English or env LANG=C for Linux default. The final look of the *.desktop file would be:

[Desktop Entry]
...
Exec=env LANG=en_US.UTF-8 /usr/bin/code %F
...

Sources:

Answered: How to exit qemu in an ESP-IDF?

Thu, 24 Jul 2025 12:27:13 +0000

In this case, qemu is launched by the IDF Monitor. Therefore, the keyboard shortcuts of the IDF Monitor must be used:

First press CTRL + T menu escape key
Then press X to exit

PS: The case of the letter makes no difference.

Answered: How to enable GCOV coverage in ESP-IDF

Thu, 24 Jul 2025 12:12:09 +0000

This problem arises because the ESP-IDF can't find the configuration of the app_trace component. Although this wasn't mentioned in the relevant docs or the gcov example, the component should be declared in the test_app/main/CMakeLists.txt file as a REQUIRED component.

Here is the correct declaration so that you can see the app_trace configs in the SDK config menu:

idf_component_register(
    SRCS ${srcs}
    INCLUDE_DIRS "."
    REQUIRES unity relay_chn app_trace
    WHOLE_ARCHIVE
)

GCOV Enablement Checklist

Make sure the and gcovr is installed by python -m pip install gcovr
Add app_trace as REQUIRED in the relevant CMakeLists.txt file
Add the --coverage compiler option for the relevant files to their specific cmake files. See Compiler Option for Gcov
Configure the App Trace component correctly to be able to collect gcov data. See Project Configuration for Gcov

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

Thu, 24 Jul 2025 10:30:23 +0000

QEMU has an option called -no-reboot (see also here), that causes the QEMU exit when the emulated target is rebooted. But since QEMU is called via idf.py, this option should be passed to qemu using the --qemu-extra-args flag as stated here.

So the final command to invoke in terminal would be like the following;

idf.py qemu --qemu-extra-args "-no-reboot"

Answered: How to add relative file links in Github or Gitea editor

Tue, 22 Jul 2025 22:03:36 +0000

Both Github and Gitea supports relative linking in their markdown editor. The relative link format is just like specifying a path in a directory:
[Some file](path/to/somefile)

Or for referring to a specific snapshot of a file:
[Some file](/blob/ref-id/path/to/somefile)

Where the ref-id can be a commit id or a branch name.

Reference:

https://stackoverflow.com/questions/7653483/github-relative-link-in-markdown-file