nodejs/node · error

: could not open output file \n

Error message

%s: could not open output file %s\n

What it means

After successfully opening the input, convert() opens the output with std::ofstream::open and checks is_open(). Failure means the destination path cannot be written. Unlike the input case, it does NOT call cleanup() here (output may simply be absent), and returns 1.

Solutions

1. Ensure the output's parent directory exists and is writable (create it in the build rule with mkdir -p).
2. Check disk space and quota on the destination volume.
3. Remove or chmod any stale read-only file occupying the output path.

import os
outdir = os.path.dirname(outfile) or '.'
if not os.path.isdir(outdir) or not os.access(outdir, os.W_OK):
    raise PermissionError(f'escapesrc output dir not writable: {outdir}')

When it happens

Trigger: outf.open(outfile) fails: the parent directory does not exist, the path is a directory, the volume is read-only or full, or the caller lacks write permission.

Common situations: Destination directory not created by the build (missing mkdir -p step); output redirected to a path the build user cannot write; disk/quota full in CI; a leftover read-only file at the output path.

Related errors

• : could not open input file \n
• T_FileStream_open failed to open
• T_FileStream_remove failed to delete
• U_FILE_ACCESS_ERROR
• Unable to create map file

AI-assisted analysis of nodejs/node@1b2de5e052 (2026-08-13). Data as JSON: /api/errors/c85b9315cd5f0046. Report an issue: GitHub.

Appendix: source

Thrown at deps/icu-small/source/tools/escapesrc/escapesrc.cpp:385

int convert(const std::string &infile, const std::string &outfile) {
  fprintf(stderr, "escapesrc: %s -> %s\n", infile.c_str(), outfile.c_str());

  std::ifstream inf;
  
  inf.open(infile.c_str(), std::ios::in);

  if(!inf.is_open()) {
    fprintf(stderr, "%s: could not open input file %s\n", prog.c_str(), infile.c_str());
    cleanup(outfile);
    return 1;
  }

  std::ofstream outf;

  outf.open(outfile.c_str(), std::ios::out);

  if(!outf.is_open()) {
    fprintf(stderr, "%s: could not open output file %s\n", prog.c_str(), outfile.c_str());
    return 1;
  }

  // TODO: any platform variations of #line?
  outf << "#line 1 \"" << infile << "\"" << '\n';

  int no = 0;
  std::string linestr;
  while( getline( inf, linestr)) {
    no++;
    if(fixLine(no, linestr)) {
      goto fail;
    }
    outf << linestr << '\n';
  }

  if(inf.eof()) {
    return 0;

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