/* * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */#include <u.h>#include <libc.h>int wrrd;voidusage(void){ fprint(2, "usage: rdwr [-w] file\n"); exits("usage");}voidmain(int argc, char **argv){ int fd; char buf[8192]; int n; ARGBEGIN{ case 'w': wrrd = 1; break; default: usage(); }ARGEND; if(argc != 1) usage(); if((fd = open(argv[0], ORDWR)) < 0) sysfatal("open: %r"); if(wrrd){ n = read(fd, buf, sizeof buf); if(n < 0) fprint(2, "read error: %r\n"); else{ write(1, buf, n); print("\n"); } } while(print("> "), (n = read(0, buf, 1000)) > 0) { seek(fd, 0, 0); if(write(fd, buf, n-1) != n-1) /* n-1: no newline */ fprint(2, "write error: %r\n"); seek(fd, 0, 0); n = read(fd, buf, sizeof buf); if(n < 0) fprint(2, "read error: %r\n"); else{ write(1, buf, n); print("\n"); } }}
/*
* This file is part of the UCB release of Plan 9. It is subject to the license
* terms in the LICENSE file found in the top-level directory of this
* distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
* part of the UCB release of Plan 9, including this file, may be copied,
* modified, propagated, or distributed except according to the terms contained
* in the LICENSE file.
*/
#include <u.h>
#include <libc.h>
int wrrd;
void
usage(void)
{
fprint(2, "usage: rdwr [-w] file\n");
exits("usage");
}
void
main(int argc, char **argv)
{
int fd;
char buf[8192];
int n;
ARGBEGIN{
case 'w':
wrrd = 1;
break;
default:
usage();
}ARGEND;
if(argc != 1)
usage();
if((fd = open(argv[0], ORDWR)) < 0)
sysfatal("open: %r");
if(wrrd){
n = read(fd, buf, sizeof buf);
if(n < 0)
fprint(2, "read error: %r\n");
else{
write(1, buf, n);
print("\n");
}
}
while(print("> "), (n = read(0, buf, 1000)) > 0) {
seek(fd, 0, 0);
if(write(fd, buf, n-1) != n-1) /* n-1: no newline */
fprint(2, "write error: %r\n");
seek(fd, 0, 0);
n = read(fd, buf, sizeof buf);
if(n < 0)
fprint(2, "read error: %r\n");
else{
write(1, buf, n);
print("\n");
}
}
}