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/// \file utils/process/system.hpp
/// Indirection to perform system calls.
///
/// The indirections exposed in this file are provided to allow unit-testing of
/// particular system behaviors (e.g. failures).  The caller of a routine in
/// this library is allowed, for testing purposes only, to explicitly replace
/// the pointers in this file with custom functions to inject a particular
/// behavior into the library code.
///
/// Do not include this header from other header files.
///
/// It may be nice to go one step further and completely abstract the library
/// functions in here to provide exception-based error reporting.

#if !defined(UTILS_PROCESS_SYSTEM_HPP)
#define UTILS_PROCESS_SYSTEM_HPP

extern "C" {
#include <unistd.h>
}

namespace utils {
namespace process {
namespace detail {


extern int (*syscall_dup2)(const int, const int);
extern pid_t (*syscall_fork)(void);
extern int (*syscall_open)(const char*, const int, ...);
extern int (*syscall_pipe)(int[2]);
extern pid_t (*syscall_waitpid)(const pid_t, int*, const int);


}  // namespace detail
}  // namespace process
}  // namespace utils

#endif  // !defined(UTILS_PROCESS_SYSTEM_HPP)