#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 */
int errno;
int /*<<< orphan*/ fprintf(int /*<<< orphan*/, char *, char *);
int /*<<< orphan*/ pclose(int /*<<< orphan*/ *);
int /*<<< orphan*/ *popen(char *, char *);
int /*<<< orphan*/ stderr;
char *strerror(int);
int syspipe(char *cmd) {
  FILE *pipe = popen(cmd, "w");
  if (!pipe) {
    fprintf(stderr, "%s\n", strerror(errno));
    return errno;
  } else {
    pclose(pipe);
    return 0;
  }
}


x86 assembly (clang, -O0):
<syspipe>:
push   %rbp
mov    %rsp,%rbp
sub    $0x20,%rsp
mov    %rdi,-0x10(%rbp)
mov    -0x10(%rbp),%rdi
lea    0xea9(%rip),%rsi
call   1050 <popen@plt>
mov    %rax,-0x18(%rbp)
cmpq   $0x0,-0x18(%rbp)
jne    11a8 <syspipe+0x68>
mov    0x2e6e(%rip),%rax
mov    (%rax),%eax
mov    %eax,-0x1c(%rbp)
mov    0x2e5a(%rip),%rax
mov    (%rax),%edi
call   1060 <strerror@plt>
mov    -0x1c(%rbp),%edi
mov    %rax,%rdx
lea    0xe70(%rip),%rsi
call   1040 <fprintf@plt>
mov    0x2e3a(%rip),%rax
mov    (%rax),%eax
mov    %eax,-0x4(%rbp)
jmp    11b8 <syspipe+0x78>
mov    -0x18(%rbp),%rdi
call   1030 <pclose@plt>
movl   $0x0,-0x4(%rbp)
mov    -0x4(%rbp),%eax
add    $0x20,%rsp
pop    %rbp
ret

x86 assembly (clang, -O2):
<syspipe>:
push   %r14
push   %rbx
push   %rax
lea    0xeb5(%rip),%rsi
call   1050 <popen@plt>
test   %rax,%rax
je     1161 <syspipe+0x21>
mov    %rax,%rdi
call   1030 <pclose@plt>
xor    %eax,%eax
jmp    118d <syspipe+0x4d>
mov    0x2e78(%rip),%rax
mov    (%rax),%ebx
mov    0x2e67(%rip),%r14
mov    (%r14),%edi
call   1060 <strerror@plt>
lea    0xe82(%rip),%rsi
mov    %ebx,%edi
mov    %rax,%rdx
call   1040 <fprintf@plt>
mov    (%r14),%eax
add    $0x8,%rsp
pop    %rbx
pop    %r14
ret

LLVM IR (-O0):
@.str = [2 x i8] c"w\00"
@stderr = global i32 0
@.str.1 = [4 x i8] c"%s\0A\00"
@errno = global i32 0
define i32 @syspipe(i8* %0) {
%2 = alloca i32
%3 = alloca i8*
%4 = alloca i32*
store i8* %0, i8** %3
%5 = load i8*, i8** %3
%6 = call i32* @popen(i8* %5, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
store i32* %6, i32** %4
%7 = load i32*, i32** %4
%8 = icmp ne i32* %7, null
br i1 %8, label %15, label %9
9: ; preds = %1
%10 = load i32, i32* @stderr
%11 = load i32, i32* @errno
%12 = call i8* @strerror(i32 %11)
%13 = call i32 @fprintf(i32 %10, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.1, i64 0, i64 0), i8* %12)
%14 = load i32, i32* @errno
store i32 %14, i32* %2
br label %18
15: ; preds = %1
%16 = load i32*, i32** %4
%17 = call i32 @pclose(i32* %16)
store i32 0, i32* %2
br label %18
18: ; preds = %15, %9
%19 = load i32, i32* %2
ret i32 %19
}

LLVM IR (-O2):
@.str = [2 x i8] c"w\00"
@stderr = global i32 0
@.str.1 = [4 x i8] c"%s\0A\00"
@errno = global i32 0
define i32 @syspipe(i8* nocapture %0) {
%2 = tail call i32* @popen(i8* %0, i8* getelementptr inbounds ([2 x i8], [2 x i8]* @.str, i64 0, i64 0))
%3 = icmp eq i32* %2, null
br i1 %3, label %4, label %10
4: ; preds = %1
%5 = load i32, i32* @stderr
%6 = load i32, i32* @errno
%7 = tail call i8* @strerror(i32 %6)
%8 = tail call i32 @fprintf(i32 %5, i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str.1, i64 0, i64 0), i8* %7)
%9 = load i32, i32* @errno
br label %12
10: ; preds = %1
%11 = tail call i32 @pclose(i32* %2)
br label %12
12: ; preds = %10, %4
%13 = phi i32 [ 0, %10 ], [ %9, %4 ]
ret i32 %13
}