/*
* This program strips the CRs from a file.  MSDOS uses CRLF for
* \n while Unix uses only a LF.  In addition, ^Z characters are
* stripped from the input file.  Unix does not use ^Z to mark the
* EOF, while some MSDOS editors put a ^Z at the end of a file.
* ^D characters are stripped from the file also.  Some PC products
* which produce Postscript output put ^Ds in the file.  Some
* Postscript printers will complain about these files and refuse
* to print them.
*/
#include <stdio.h>
#include <errno.h>
#include <string.h>

#define CTRL_D	'\004'	/* EOT */
#define CTRL_M	'\015'	/* CR */
#define CTRL_Z	'\032'	/* SUB */

int main(int argc, char **argv)
{
    FILE *infp;
    FILE *outfp;
    char buffer[2];

    if (argc > 2) {
        /* don't translate CRLF into LF when reading */
        if ((infp = fopen(argv[1], "rb")) == NULL) {
            // perror(strerror(errno));
			fprintf(stderr, "Open file %s has errno %d %s\n", argv[1], errno, strerror(errno));
            return 1;
        }

        /* don't translate LF into CRLF when writing */
        if ((outfp = fopen(argv[2], "wb")) == NULL) {
            // perror(strerror(errno));
			fprintf(stderr, "Open file %s has errno %d %s\n", argv[2], errno, strerror(errno));
            return 1;
        }
    }
    else
    {
        fprintf(stderr, "Usage: dos2unix [infile] [outfile]\n");
        return 2;
    }

    while (fread(buffer, sizeof (char), 1, infp) == 1)
        if ( (buffer[0] != CTRL_D) && (buffer[0] != CTRL_M) && (buffer[0] != CTRL_Z) )
            (void) fputc(buffer[0], outfp);

    return 0;
}