add thread_array_management

randomstring.c

@@ -0,0 +1,21 @@
+// returns symbols from 32 to 126 read from /dev/urandom, not thread-safe
+// s - length of data with trailing zero
+
+#include <sys/random.h>
+char *randstring(size_t *s){
+    static char buf[256];
+    char rbuf[255];
+    ssize_t L = getrandom(rbuf, 255, 0);
+    if(L < 1){
+        *s = 0;
+        return NULL;
+    }
+    size_t total = 0;
+    for(size_t x = 0; x < (size_t)L; ++x){
+        char s = rbuf[x];
+        if(s > 31 && s < 127) buf[total++] = s;
+    }
+    buf[total++] = 0;
+    *s = total;
+    return buf;
+}