#define NULL ((void *)0)
typedef unsigned long size_t; // Customize by platform.
typedef long intptr_t;
typedef unsigned long uintptr_t;
typedef long scalar_t__; // Either arithmetic or pointer type.
/* By default, we understand bool (as a convenience). */
typedef int bool;
#define false 0
#define true 1

/* Forward declarations */

/* Type definitions */
typedef int /*<<< orphan*/ FILE;

/* Variables and functions */
scalar_t__ fgets(char *, int, int /*<<< orphan*/ *);
int /*<<< orphan*/ pclose(int /*<<< orphan*/ *);
int /*<<< orphan*/ *popen(char *, char *);
int /*<<< orphan*/ printf(char *, char *);
int main(void) {
  FILE *fd;
  char temp[256];
  fd = popen(
      "tac /etc/ppp/connect-errors | grep '['CONNECT'|'CARRIER']' | head -1",
      "r");
  while (fgets(temp, 256, fd)) {
    printf("%s", temp);
  }
  pclose(fd);
  return 0;
}


x86 assembly (clang, -O0):
<main>:
push   %rbp
mov    %rsp,%rbp
sub    $0x110,%rsp
movl   $0x0,-0x4(%rbp)
lea    0xea7(%rip),%rdi
lea    0xee5(%rip),%rsi
call   1060 <popen@plt>
mov    %rax,-0x10(%rbp)
lea    -0x110(%rbp),%rdi
mov    -0x10(%rbp),%rdx
mov    $0x100,%esi
call   1050 <fgets@plt>
cmp    $0x0,%rax
je     11a0 <main+0x60>
lea    -0x110(%rbp),%rsi
lea    0xeb1(%rip),%rdi
call   1030 <printf@plt>
jmp    1169 <main+0x29>
mov    -0x10(%rbp),%rdi
call   1040 <pclose@plt>
xor    %eax,%eax
add    $0x110,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<main>:
push   %r15
push   %r14
push   %rbx
sub    $0x100,%rsp
lea    0xead(%rip),%rdi
lea    0xeeb(%rip),%rsi
call   1060 <popen@plt>
mov    %rax,%r15
mov    %rsp,%rdi
mov    $0x100,%esi
mov    %rax,%rdx
call   1050 <fgets@plt>
test   %rax,%rax
je     11b0 <main+0x70>
lea    0xec9(%rip),%r14
mov    %rsp,%rbx
cs nopw 0x0(%rax,%rax,1)
nopl   0x0(%rax,%rax,1)
mov    %r14,%rdi
mov    %rbx,%rsi
call   1030 <printf@plt>
mov    %rbx,%rdi
mov    $0x100,%esi
mov    %r15,%rdx
call   1050 <fgets@plt>
test   %rax,%rax
jne    1190 <main+0x50>
mov    %r15,%rdi
call   1040 <pclose@plt>
xor    %eax,%eax
add    $0x100,%rsp
pop    %rbx
pop    %r14
pop    %r15
ret

LLVM IR (-O0):
@.str = [69 x i8] c"tac /etc/ppp/connect-errors | grep '['CONNECT'|'CARRIER']' | head -1\00"
@.str.1 = [2 x i8] c"r\00"
@.str.2 = [3 x i8] c"%s\00"
define i32 @main() {
%1 = alloca i32
%2 = alloca i32*
%3 = alloca [256 x i8]
store i32 0, i32* %1
%4 = call i32* @popen(i8* getelementptr inbounds ([69 x i8], [69 x i8]* @.str, i64 0, i64 0), i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
store i32* %4, i32** %2
br label %5
5: ; preds = %10, %0
%6 = getelementptr inbounds [256 x i8], [256 x i8]* %3, i64 0, i64 0
%7 = load i32*, i32** %2
%8 = call i64 @fgets(i8* %6, i32 256, i32* %7)
%9 = icmp ne i64 %8, 0
br i1 %9, label %10, label %13
10: ; preds = %5
%11 = getelementptr inbounds [256 x i8], [256 x i8]* %3, i64 0, i64 0
%12 = call i32 @printf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.2, i64 0, i64 0), i8* %11)
br label %5
13: ; preds = %5
%14 = load i32*, i32** %2
%15 = call i32 @pclose(i32* %14)
ret i32 0
}

LLVM IR (-O2):
@.str = [69 x i8] c"tac /etc/ppp/connect-errors | grep '['CONNECT'|'CARRIER']' | head -1\00"
@.str.1 = [2 x i8] c"r\00"
@.str.2 = [3 x i8] c"%s\00"
define i32 @main() {
%1 = alloca [256 x i8]
%2 = getelementptr inbounds [256 x i8], [256 x i8]* %1, i64 0, i64 0
%3 = tail call i32* @popen(i8* getelementptr inbounds ([69 x i8], [69 x i8]* @.str, i64 0, i64 0), i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str.1, i64 0, i64 0))
%4 = call i64 @fgets(i8* %2, i32 256, i32* %3)
%5 = icmp eq i64 %4, 0
br i1 %5, label %10, label %6
6: ; preds = %0, %6
%7 = call i32 @printf(i8* getelementptr inbounds ([3 x i8], [3 x i8]* @.str.2, i64 0, i64 0), i8* %2)
%8 = call i64 @fgets(i8* %2, i32 256, i32* %3)
%9 = icmp eq i64 %8, 0
br i1 %9, label %10, label %6
10: ; preds = %6, %0
%11 = call i32 @pclose(i32* %3)
ret i32 0
}