How to print a uint64_t variable?

[Don]

Although this is a similar question to Case ID: 116570 "sprintf with a uint64_t variable?"
I am unable to use the answer:
I cannot find LDFLAGS.
I can find... SDK/external/segger_rtt/SEGGER_RTT_Syscalls_SES.c:#include "__libc.h"

TEST CODE:

uint64_t timestamp = 1422028920000;
char buffer[32];
snprintf(buffer, sizeof(buffer), "%" PRIu64 "", timestamp);
NRF_LOG_INFO("TEST PRINT ? 1422028920000 == %s", buffer);

OUTPUT:

app: TEST PRINT ? 1422028920000 == u

I am using nRF5_SDK_16.0.0
Code derived from examples/ble_peripheral/ble_app_hrs/pca10056/s140/

#include
#include
#include "nordic_common.h"
#include "nrf.h"
#include "nrf_sdm.h"
#include "app_error.h"
#include "ble.h"
#include "ble_err.h"
#include "ble_hci.h"
#include "ble_srv_common.h"
#include "ble_advdata.h"
#include "ble_advertising.h"
#include "ble_bas.h"
#include "ble_hrs.h"
#include "ble_dis.h"
#include "ble_conn_params.h"
#include "sensorsim.h"
#include "nrf_sdh.h"
#include "nrf_sdh_ble.h"
#include "nrf_sdh_soc.h"
#include "app_timer.h"
#include "bsp_btn_ble.h"
#include "peer_manager.h"
#include "peer_manager_handler.h"
#include "fds.h"
#include "nrf_ble_gatt.h"
#include "nrf_ble_lesc.h"
#include "nrf_ble_qwr.h"
#include "ble_conn_state.h"
#include "nrf_pwr_mgmt.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

#include "my_service.h"
#include
#include
#include "ble.h"
#include "ble_srv_common.h"
#include "my_control.h"
#include "sdk_common.h"
#include
#include "nrf_gpio.h"

[Nguyen Hoan Hoang]

which compiler ? for GCC you need to use newlib for that.  nano lib doesn't work.

[Don]

Thanks,

I am using whatever default  compiler is provided by  SEGGER Embedded Studio for ARM V4.30. What would that be?
Perhaps you can suggest on introduction to using SEGGER and selecting suitable libraries? I cant see any reference to "nano lib".
Could I download "newlib" from somewhere and add a it to the project by editing my_project.emProject  ?

In the meantime I re-invented a rough wheel, which works using printf:

/** String representation of uint64_t
* char[] output buffer
* length of output buffer
* uint64_t input
* (radix == 10) | (radix == 16)
*/
void toString_uint64_t(char * output, const int length, uint64_t input, const int radix ) {
if ( (radix != 10) & (radix != 16) ) {
output[0] = 'R';
output[1] = 'A';
output[2] = 'D';
output[3] = 'I';
output[4] = 'X';
output[5] = '?';
output[6] = 0; // null terminator
return;
}
const char digits[] = {'0', '1','2','3','4','5','6','7','8','9','A','B','C','D','E','F' };
int head = length;
for(int i = 0; ((i < length) & (input > 0)); i++ ) {
head--;
char digit = digits[ input % radix ];
output[head] = digit;
input /= radix;
}
// shift output and add string terminator:
int count = length - head;
for( int i = 0; (i < count); i++ ) {
output[i] = output[ head + i ];
}
for( int i = count; (i < length); i++ ) {
output[i] = 0; // null terminator
}

}

[Nguyen Hoan Hoang]

I am not using SES but I know SES uses GCC.  You'll have to look for it in their settings.  In Eclipse GCC you can select either newlib or nano in the linker settings.