Process

while true; do
sleep 1 &
...your stuff here...
wait # for sleep
done

key      equivalent-key-combinations
Up       alt + \      or  alt + k
Down     alt + /      or  alt + j
Left     alt + <      or  alt + h
Right    alt + >      or  alt + l (lower case L)
PgUp     alt + Up     or  alt + ctrl + k
PgDn     alt + Down   or  alt + ctrl + j
Home     alt + Left   or  alt + ctrl + h
End      alt + Right  or  alt + ctrl + l

backtrace
backtrace_symbols
backtrace_symbols_fd

#include <execinfo.h>
#include <stdio.h>
#include <stdlib.h>

void print_trace() {
    static const int SIZE = 10;

    void* buffer[SIZE];
    char** strings;
    int size, i;

    size = backtrace(buffer, SIZE);
    strings = backtrace_symbols(buffer, size);
    if (strings != NULL) {
        printf("Obtained %d stack frames.\n", size);
        for (i = 0; i < size; ++i)
            printf("%s\n", strings[i]);
        free(strings);
    }
}