c - Alternative and probable better way to printf -


i writing string gstring using printf as:

char *string<i>  /*where string<i> stands string1, string2 , on*/  g_string_append_printf (ustring, "@%s{%s,\n",string1, string0); if( strlen(string2)!=0 ||string2!=null)  g_string_append_printf (ustring,"\tauthor=\"%s\",\n", string2); if( strlen(string3)!=0 ||string3!=null)  g_string_append_printf (ustring,"\tyear=\"%s\",\n", string3); if( strlen(string4)!=0 ||string4!=null) g_string_append_printf (ustring, "\ttitle=\"%s\",\n", string4);

glib's not important here. consider as

printf ("\tauthor=\"%s\",\n", string<i>)

when works rather fine, seems not best way(i have strings string<1> string<30>) , looking better way.

points consider

  1. any string may empty/null, checked every line before printf.

  2. would better if complete print thing works function

any better way of implementing this?

eliminate duplication checks if string null or empty wrapping in function:

void conditionally_append_string(char* out, const char* fmt, const char* in) {     /* check null before dereferencing.        check if first character not null terminator        instead of invoking strlen(). */     if (in && *in)     {         g_string_append_printf (out, fmt, in);     } }  conditionally_append_string(ustring, "@%s{\n",             string0); conditionally_append_string(ustring, "%s,\n",              string1); conditionally_append_string(ustring, "\tauthor=\"%s\",\n", string2);

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