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POConcatenate text with numbers in a function with variable number of parameters
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copied!<p>I made a function in C, that concatenates a variable number of strings. That's my code:</p> <pre><code>char* texto(const char* s, ...){ va_list args; char *tmp; char *res; size_t len = strlen(s); // pega um handle ao início da lista de parâmetros va_start(args, s); // calcula o tamanho total de todas as strings - pega o próximo parâmetro da lista, até chegar no NULL while ((tmp = va_arg(args, char*))){ len += strlen(tmp); } va_end(args); res = malloc(len+1); if (!res){ fprintf(stderr, "Erro ao alocar string. Função 'texto'\n"); exit(EXIT_FAILURE); } // cria a string concatenada strcpy(res, s); va_start(args, s); // pega o próximo parâmetro da lista, até chegar no NULL while ((tmp = va_arg(args, char*))){ strcat(res, tmp); } va_end(args); return res; } </code></pre> <p>I'm using like this:</p> <pre><code>char* txt = texto("a", "b", "c", "d", "e", NULL); //txt is now: "abcde" </code></pre> <p>It works fine. But I can't pass numeric parameters to this function, only strings. I need to change the function to work like this:</p> <pre><code>char* txt = texto("a", "b", 1, "d", 4.5, "e", NULL); //txt is now: "ab1d4.5e" </code></pre> <p>How can I do that? How I get parameters with diferent types using va_arg()?</p> <p>The solution I found until now is create a function int2str():</p> <pre><code>inline char* int2str(int inteiro){ char* str = malloc(10); sprintf(str, "%d", inteiro); return str; } </code></pre> <p>But I have to use this way:</p> <pre><code>char* txtnum = int2str(23); char* txt = texto("a", txtnum, NULL); free(txtnum); </code></pre> <p>otherwise, I got a memory leak...</p> <p>I could use the function int2str() inside the function texto() but I don't know how to check the type of the parameters!</p> <p>Ps.: I'm using C, not C++ for my code.</p>

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