devproc: can't wait for ourselfs to stop (thanks Shamar)

[plan9front.git] / sys / src / cmd / read.c

diff --git a/sys/src/cmd/read.c b/sys/src/cmd/read.c
old mode 100755 (executable)
new mode 100644 (file)
index 56d8013..6377fdc
--- a/sys/src/cmd/read.c
+++ b/sys/src/cmd/read.c
@@ -3,6 +3,7 @@
 
 int    multi;
 int    nlines;
+vlong  nchars;
 char   *status = nil;
 
 int
@@ -52,30 +53,61 @@ lines(int fd, char *file)
        }while(multi || --nlines>0);
 }
 
+void
+chars(int fd, char *file)
+{
+       char buf[8*1024];
+       vlong m;
+       int n;
+
+       for(m = 0; m < nchars; m += n){
+               n = sizeof(buf);
+               if(n > (nchars - m))
+                       n = nchars - m;
+               if((n = read(fd, buf, n)) < 0){
+                       fprint(2, "read: error reading %s: %r\n", file);
+                       exits("read error");
+               }
+               if(n == 0){
+                       if(m == 0)
+                               status = "eof";
+                       break;
+               }
+               write(1, buf, n);
+       }
+}
+
+void
+usage(void)
+{
+       fprint(2, "usage: read [-m] [-n nlines] [-c nbytes] [files...]\n");
+       exits("usage");
+}
+
 void
 main(int argc, char *argv[])
 {
+       void (*proc)(int, char*);
        int i, fd;
-       char *s;
 
+       proc = lines;
        ARGBEGIN{
+       case 'c':
+               nchars = atoll(EARGF(usage()));
+               proc = chars;
+               break;
+       case 'n':
+               nlines = atoi(EARGF(usage()));
+               break;
        case 'm':
                multi = 1;
                break;
-       case 'n':
-               s = ARGF();
-               if(s){
-                       nlines = atoi(s);
-                       break;
-               }
-               /* fall through */
        default:
-               fprint(2, "usage: read [-m] [-n nlines] [files...]\n");
-               exits("usage");
+               usage();
        }ARGEND
 
        if(argc == 0)
-               lines(0, "<stdin>");
+               (*proc)(0, "<stdin>");
        else
                for(i=0; i<argc; i++){
                        fd = open(argv[i], OREAD);
@@ -83,7 +115,7 @@ main(int argc, char *argv[])
                                fprint(2, "read: can't open %s: %r\n", argv[i]);
                                exits("open");
                        }
-                       lines(fd, argv[i]);
+                       (*proc)(fd, argv[i]);
                        close(fd);
                }