llvm-toolchain-10/libcxx/utils/cat_files.py

46 lines
1.3 KiB
Python
Executable File

#!/usr/bin/env python
#===----------------------------------------------------------------------===##
#
# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
# See https://llvm.org/LICENSE.txt for license information.
# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
#
#===----------------------------------------------------------------------===##
from argparse import ArgumentParser
import sys
def print_and_exit(msg):
sys.stderr.write(msg + '\n')
sys.exit(1)
def main():
parser = ArgumentParser(
description="Concatenate two files into a single file")
parser.add_argument(
'-o', '--output', dest='output', required=True,
help='The output file. stdout is used if not given',
type=str, action='store')
parser.add_argument(
'files', metavar='files', nargs='+',
help='The files to concatenate')
args = parser.parse_args()
if len(args.files) < 2:
print_and_exit('fewer than 2 inputs provided')
data = ''
for filename in args.files:
with open(filename, 'r') as f:
data += f.read()
if len(data) != 0 and data[-1] != '\n':
data += '\n'
assert len(data) > 0 and "cannot cat empty files"
with open(args.output, 'w') as f:
f.write(data)
if __name__ == '__main__':
main()
sys.exit(0)