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copied!<p>The following code will give you a hex dump of arbitrary memory from within your code.</p> <pre><code>#include <stdio.h> void hexDump (char *desc, void *addr, int len) { int i; unsigned char buff[17]; unsigned char *pc = (unsigned char*)addr; // Output description if given. if (desc != NULL) printf ("%s:\n", desc); if (len == 0) { printf(" ZERO LENGTH\n"); return; } if (len < 0) { printf(" NEGATIVE LENGTH: %i\n",len); return; } // Process every byte in the data. for (i = 0; i < len; i++) { // Multiple of 16 means new line (with line offset). if ((i % 16) == 0) { // Just don't print ASCII for the zeroth line. if (i != 0) printf (" %s\n", buff); // Output the offset. printf (" %04x ", i); } // Now the hex code for the specific character. printf (" %02x", pc[i]); // And store a printable ASCII character for later. if ((pc[i] < 0x20) || (pc[i] > 0x7e)) buff[i % 16] = '.'; else buff[i % 16] = pc[i]; buff[(i % 16) + 1] = '\0'; } // Pad out last line if not exactly 16 characters. while ((i % 16) != 0) { printf (" "); i++; } // And print the final ASCII bit. printf (" %s\n", buff); } int main (int argc, char *argv[]) { char my_str[] = "a char string greater than 16 chars"; hexDump ("my_str", &my_str, sizeof (my_str)); return 0; } </code></pre> <p>You pass into <code>hexDump</code> a description, memory address and length, and it will output a hex dump (including character data) for examination. When you run it with the included <code>main</code>, the output is:</p> <pre><code>my_str: 0000 61 20 63 68 61 72 20 73 74 72 69 6e 67 20 67 72 a char string gr 0010 65 61 74 65 72 20 74 68 61 6e 20 31 36 20 63 68 eater than 16 ch 0020 61 72 73 00 ars. </code></pre>

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