chromium/third_party/breakpad/breakpad/src/common/linux/scoped_pipe.h

// Copyright 2022 Google LLC
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#ifndef COMMON_LINUX_SCOPED_PIPE_H_
#define COMMON_LINUX_SCOPED_PIPE_H_

#include <stdint.h>
#include <string>

namespace google_breakpad {

// Small RAII wrapper for a pipe pair.
//
// Example (both ends of pipe in same process):
//   ScopedPipe tmp;
//   std::string line;
//   if (tmp.Init() && tmp.Write(bytes, bytes_len)) {
//     tmp.CloseWriteFd();
//     while (tmp.ReadLine(&line)) {
//       std::cerr << line << std::endl;
//     }
//   }
//
// Example (reading output from a child process):
//   ScopedPipe tmp;
//   if (fork()) {
//     // Parent process, read from the read end of the pipe.
//     std::string line;
//     while (tmp.ReadLine(line)) {
//       // Process output...
//     }
//     // Close read pipe once done processing the output that we wanted, this
//     // should ensure that the child process exits even if we didn't read all
//     // of the output.
//     tmp.CloseReadFd();
//     // Parent process should handle waiting for child to exit here...
//   } else {
//     // Child process, close the read fd and dup the write fd before exec'ing.
//     tmp.CloseReadFd();
//     tmp.Dup2WriteFd(STDOUT_FILENO);
//     tmp.Dup2WriteFd(STDERR_FILENO);
//     execl("some-command", "some-arguments");
//   }
class ScopedPipe { … };

}  // namespace google_breakpad

#endif // COMMON_LINUX_SCOPED_PIPE_H_