Bell 32V development

[unix-history] / usr / src / cmd / cat.c

/*
* Concatenate files.
*/

#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>

char    stdbuf[BUFSIZ];

main(argc, argv)
char **argv;
{
       int fflg = 0;
       register FILE *fi;
       register c;
       int dev, ino = -1;
       struct stat statb;

       setbuf(stdout, stdbuf);
       for( ; argc>1 && argv[1][0]=='-'; argc--,argv++) {
               switch(argv[1][1]) {
               case 0:
                       break;
               case 'u':
                       setbuf(stdout, (char *)NULL);
                       continue;
               }
               break;
       }
       fstat(fileno(stdout), &statb);
       statb.st_mode &= S_IFMT;
       if (statb.st_mode!=S_IFCHR && statb.st_mode!=S_IFBLK) {
               dev = statb.st_dev;
               ino = statb.st_ino;
       }
       if (argc < 2) {
               argc = 2;
               fflg++;
       }
       while (--argc > 0) {
               if (fflg || (*++argv)[0]=='-' && (*argv)[1]=='\0')
                       fi = stdin;
               else {
                       if ((fi = fopen(*argv, "r")) == NULL) {
                               fprintf(stderr, "cat: can't open %s\n", *argv);
                               continue;
                       }
               }
               fstat(fileno(fi), &statb);
               if (statb.st_dev==dev && statb.st_ino==ino) {
                       fprintf(stderr, "cat: input %s is output\n",
                          fflg?"-": *argv);
                       fclose(fi);
                       continue;
               }
               while ((c = getc(fi)) != EOF)
                       putchar(c);
               if (fi!=stdin)
                       fclose(fi);
       }
       return(0);
}