Script started on Wed 01 Feb 2017 11:26:50 AM PST
[perkins@D-172-16-9-157 11-gdb-files]$ emacs reverse.c &
[1] 2912
[perkins@D-172-16-9-157 11-gdb-files]$ ./reverse 
Please enter a string: hello
The original string was:   >hello
<
Backwards, that string is: ><
Thank you for trying our program.
[perkins@D-172-16-9-157 11-gdb-files]$ gdb ./reverse
GNU gdb (GDB) Red Hat Enterprise Linux 7.11-67.el7
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from ./reverse...done.
(gdb) break main
Breakpoint 1 at 0x4007ab: file reverse.c, line 43.
(gdb) run
Starting program: /home/perkins/cse374/11-gdb-files/reverse 
Missing separate debuginfos, use: debuginfo-install glibc-2.17-157.el7_3.1.x86_64

Breakpoint 1, main () at reverse.c:43
43	  printf("Please enter a string: ");
(gdb) list
38	/* Ask the user for a string, then print it forwards and backwards.     */
39	int main() {
40	  char line[MAX_STR];    /* original input line */
41	  char * rev_line;       /* backwards copy from reverse function */
42	
43	  printf("Please enter a string: ");
44	  fgets(line, MAX_STR, stdin);
45	  rev_line = reverse(line);
46	  printf("The original string was:   >%s<\n", line);
47	  printf("Backwards, that string is: >%s<\n", rev_line);
(gdb) n
44	  fgets(line, MAX_STR, stdin);
(gdb) n
Please enter a string: hello
45	  rev_line = reverse(line);
(gdb) p line
$1 = "hello\n\000\000\275ȫ\367\377\177\000\000v\332\377\377\377\177\000\000\000\000\000\000\000\000\000\000\001\000\000\000\000\000\000\000\377\262\360\000\000\000\000\000\001\000\000\000\000\000\000\000m\b@", '\000' <repeats 21 times>, " \b@\000\000\000\000\000\360\005@\000\000\000\000\000p\331\377\377"
(gdb) quit
A debugging session is active.

	Inferior 1 [process 3009] will be killed.

Quit anyway? (y or n) y
[perkins@D-172-16-9-157 11-gdb-files]$ gcc -Wall -g -std=c11 -o reverse reverse.c
[perkins@D-172-16-9-157 11-gdb-files]$ ./reverse 
Please enter a string: hello
The original string was:   >hello<
Backwards, that string is: ><
Thank you for trying our program.
[perkins@D-172-16-9-157 11-gdb-files]$ gdb ./reverse
GNU gdb (GDB) Red Hat Enterprise Linux 7.11-67.el7
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.  Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-redhat-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
Reading symbols from ./reverse...done.
(gdb) break reverse
Breakpoint 1 at 0x4006f2: file reverse.c, line 14.
(gdb) run
Starting program: /home/perkins/cse374/11-gdb-files/reverse 
Missing separate debuginfos, use: debuginfo-install glibc-2.17-157.el7_3.1.x86_64
Please enter a string: hello

Breakpoint 1, reverse (s=0x7fffffffd820 "hello") at reverse.c:14
14	  char * result = NULL;            /* the reversed string */
(gdb) list
9	#include <stdlib.h>
10	#include <string.h>
11	
12	/* Return a new string with the contents of s backwards */
13	char * reverse(char * s) {
14	  char * result = NULL;            /* the reversed string */
15	  int L, R;
16	  char ch;
17	
18	  /* allocate space for copy */
(gdb) p s
$1 = 0x7fffffffd820 "hello"
(gdb) p result
$2 = 0x0
(gdb) p L
$3 = 32767
(gdb) p R
$4 = -134225592
(gdb) p /x L
$5 = 0x7fff
(gdb) p /x R
$6 = 0xf7ffe148
(gdb) s
19	  int size = strlen(s)+1;
(gdb) 
20	  result = (char *)malloc(size);
(gdb) 
23	  strcpy(result, s);
(gdb) 
25	  L = 0;
(gdb) 
26	  R = strlen(result);
(gdb) 
27	  while (L < R) {
(gdb) list
22	  /* copy original string then reverse and return the copy */
23	  strcpy(result, s);
24	
25	  L = 0;
26	  R = strlen(result);
27	  while (L < R) {
28	    ch = result[L];
29	    result[L] = result[R];
30	    result[R] = ch;
31	    L++; R--;
(gdb) p s
$7 = 0x7fffffffd820 "hello"
(gdb) p result
$8 = 0x602010 "hello"
(gdb) 
$9 = 0x602010 "hello"
(gdb) p L
$10 = 0
(gdb) p R
$11 = 5
(gdb) break 27
Breakpoint 2 at 0x400746: file reverse.c, line 27.
(gdb) cont
Continuing.
The original string was:   >hello<
Backwards, that string is: ><
Thank you for trying our program.
[Inferior 1 (process 3031) exited normally]
(gdb) list
32	  }
33	
34	  return result;
35	}
36	
37	
38	/* Ask the user for a string, then print it forwards and backwards.     */
39	int main() {
40	  char line[MAX_STR];    /* original input line */
41	  char * rev_line;       /* backwards copy from reverse function */
(gdb) run
Starting program: /home/perkins/cse374/11-gdb-files/reverse 
Please enter a string: hello

Breakpoint 1, reverse (s=0x7fffffffd820 "hello") at reverse.c:14
14	  char * result = NULL;            /* the reversed string */
(gdb) list
9	#include <stdlib.h>
10	#include <string.h>
11	
12	/* Return a new string with the contents of s backwards */
13	char * reverse(char * s) {
14	  char * result = NULL;            /* the reversed string */
15	  int L, R;
16	  char ch;
17	
18	  /* allocate space for copy */
(gdb) s
19	  int size = strlen(s)+1;
(gdb) s
20	  result = (char *)malloc(size);
(gdb) s
23	  strcpy(result, s);
(gdb) s
25	  L = 0;
(gdb) s
26	  R = strlen(result);
(gdb) s

Breakpoint 2, reverse (s=0x7fffffffd820 "hello") at reverse.c:27
27	  while (L < R) {
(gdb) s
28	    ch = result[L];
(gdb) s
29	    result[L] = result[R];
(gdb) s
30	    result[R] = ch;
(gdb) s
31	    L++; R--;
(gdb) s
27	  while (L < R) {
(gdb) p result
$12 = 0x602010 ""
(gdb) p result[5]
$13 = 104 'h'
(gdb) p result[4]
$14 = 111 'o'
(gdb) p result[0]
$15 = 0 '\000'
(gdb) quit
A debugging session is active.

	Inferior 1 [process 3070] will be killed.

Quit anyway? (y or n) y
[perkins@D-172-16-9-157 11-gdb-files]$ gcc -Wall -g -std=c11 -o reverse reverse.c
[perkins@D-172-16-9-157 11-gdb-files]$ ./reverse 
Please enter a string: does it work now???
The original string was:   >does it work now???<
Backwards, that string is: >???won krow ti seod<
Thank you for trying our program.
[perkins@D-172-16-9-157 11-gdb-files]$ ./reverse 
Please enter a string: hello
The original string was:   >hello<
Backwards, that string is: >olleh<
Thank you for trying our program.
[perkins@D-172-16-9-157 11-gdb-files]$ ./reverse 
Please enter a string: goodbye
The original string was:   >goodbye<
Backwards, that string is: >eybdoog<
Thank you for trying our program.
[perkins@D-172-16-9-157 11-gdb-files]$ ./clint.py reverse.c
reverse.c:23:  Almost always, snprintf is better than strcpy  [runtime/printf] [4]
reverse.c:31:  More than one command on the same line  [whitespace/newline] [4]
Done processing reverse.c
Total errors found: 2
[perkins@D-172-16-9-157 11-gdb-files]$ ./clint.py reverse.c
reverse.c:31:  Line ends in whitespace.  Consider deleting these extra spaces.  [whitespace/end_of_line] [4]
Done processing reverse.c
Total errors found: 1
[perkins@D-172-16-9-157 11-gdb-files]$ ./clint.py reverse.c
Done processing reverse.c
Total errors found: 0
[perkins@D-172-16-9-157 11-gdb-files]$ exit
exit

Script done on Wed 01 Feb 2017 12:22:03 PM PST