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POJunk Characters Outputted After Parsing From STDIN in C
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copied!<p>I am getting a junk character to be output at the very end of some text that I read in:</p> <pre><code>hum 1345342342 ~Users/Documents ecabd459 //line that was read in from stdin event action: hum_? event timestamp: 1345342342 event path: ~Users/Documents event hash: ecabd459 </code></pre> <p>At the end of the event action value there is a '_?' garbage character that is output as well. That can be rectified by setting the variable's last position to the null terminator (<code>event.action[3] = '\0'</code>) which is all well and good, but I am perplexed by the fact that the other char array <code>event.hash</code> does not exhibit this type of behavior. I am creating/printing them in an identical manner, yet hash does not behave the same. </p> <p><strong>Note:</strong> I was considering maybe this was due to the hash value being followed strictly by a newline character(which I get rid of by the way), so I tested my program with re-ordered input to no avail (that is, added an additional space and word after the hash value's position on the line).</p> <p>The relevant code is below:</p> <pre><code>struct Event{ char action[4]; long timestamp; char* path; char hash[9]; }; // parse line and return an Event struct struct Event parseLineIntoEvent(char* line) { struct Event event; char* lineSegment; int i = 0; lineSegment = strtok(line, " "); while (lineSegment != NULL) { if (i > 3) { printf("WARNING: input format error!\n"); break; } if (i == 0) strncpy(event.action, lineSegment, sizeof(event.action)-1); else if(i == 1) event.timestamp = atoi(lineSegment); else if(i == 2) { event.path = malloc(sizeof(lineSegment)); strcpy(event.path, lineSegment); } else if(i == 3) strncpy(event.hash, lineSegment, sizeof(event.hash)-1); lineSegment = strtok(NULL, " "); i++; } // while return event; } // parseLineIntoEvent() int main (int argc, const char * argv[]) { //... printf("%s\n",line); //prints original line that was read in from stdin struct Event event = parseLineIntoEvent(line); printf("event action: %s\n", event.action); printf("event timestamp: %lu\n", event.timestamp); printf("event path: %s\n", event.path); printf("event hash: %s\n", event.hash); free(event.path); free(line); //... return 0; } </code></pre> <p><strong>EDIT:</strong> I read in a line with this function, which gets rid of the newline character:</p> <pre><code>// read in line from stdin, eliminating newline character if present char* getLineFromStdin() { char *text; int textSize = 50*sizeof(char); text = malloc(textSize); if ( fgets(text, textSize, stdin) != NULL ) { char *newline = strchr(text, '\n'); // search for newline character if ( newline != NULL ) { *newline = '\0'; // overwrite trailing newline } } return text; } </code></pre> <p>Thanks in advance!</p>

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