#!/usr/bin/env python
import argparse
import sys
from jtutils import fix_broken_pipe

def readCL():
    parser = argparse.ArgumentParser()
    parser.add_argument("infiles",default=[sys.stdin],nargs="*");
    args = parser.parse_args()
    return args.infiles

if __name__ == "__main__":
    infiles = readCL()
    fix_broken_pipe()
    hdr = None
    for f in infiles:
        with open(f) as f_in:
            this_hdr = f_in.readline()
            if hdr == None:
                hdr = this_hdr
                sys.stdout.write(hdr)
            if (this_hdr != hdr):
                raise Exception("incompatible headers: " + hdr + "\n" + this_hdr)
            sys.stdout.write(f_in.read())
