BSD 4_1_snap release

[unix-history] / usr / src / libc / stdio / fseek.c

diff --git a/usr/src/libc/stdio/fseek.c b/usr/src/libc/stdio/fseek.c
index ecbda88..5347996 100644 (file)
--- a/usr/src/libc/stdio/fseek.c
+++ b/usr/src/libc/stdio/fseek.c
@@ -1,3 +1,4 @@
+/* @(#)fseek.c 4.2 (Berkeley) 3/9/81 */

 /*
  * Seek for standard library.  Coordinates with buffering.
  */
 /*
  * Seek for standard library.  Coordinates with buffering.
  */


@@ -7,35 +8,41 @@
 long lseek();
 
 fseek(iop, offset, ptrname)
 long lseek();
 
 fseek(iop, offset, ptrname)

-       register FILE *iop;
-       long offset;
+FILE *iop;
+long offset;

 {
 {

-       register int c;
+       register resync, c;

        long p;
 
        iop->_flag &= ~_IOEOF;
        long p;
 
        iop->_flag &= ~_IOEOF;

-       if (iop->_flag & _IOREAD) {
-               if (ptrname < 2 && iop->_base && !(iop->_flag&_IONBF)) {
+       if (iop->_flag&_IOREAD) {
+               if (ptrname<2 && iop->_base &&
+                       !(iop->_flag&_IONBF)) {

                        c = iop->_cnt;
                        p = offset;
                        c = iop->_cnt;
                        p = offset;

-                       if (ptrname == 0)
-                               p += c - lseek(fileno(iop), 0L, 1);
+                       if (ptrname==0)
+                               p += c - lseek(fileno(iop),0L,1);

                        else
                                offset -= c;
                        else
                                offset -= c;

-                       if (!(iop->_flag&_IORW) && c > 0 && p <= c
-                           && p >= iop->_base - iop->_ptr){
-                               iop->_ptr += (int) p;
-                               iop->_cnt -= (int) p;
+                       if(!(iop->_flag&_IORW) && c>0&&p<=c
+                           && p>=iop->_base-iop->_ptr){
+                               iop->_ptr += (int)p;
+                               iop->_cnt -= (int)p;

                                return(0);
                        }
                                return(0);
                        }

-               }
+                       resync = offset&01;
+               } else 
+                       resync = 0;

                if (iop->_flag & _IORW) {
                        iop->_ptr = iop->_base;
                        iop->_flag &= ~_IOREAD;
                }
                if (iop->_flag & _IORW) {
                        iop->_ptr = iop->_base;
                        iop->_flag &= ~_IOREAD;
                }

-               p = lseek(fileno(iop), offset, ptrname);
+               p = lseek(fileno(iop), offset-resync, ptrname);

                iop->_cnt = 0;
                iop->_cnt = 0;

-       } else if(iop->_flag & (_IOWRT|_IORW)) {
+               if (resync)
+                       getc(iop);
+       }
+       else if (iop->_flag & (_IOWRT|_IORW)) {

                fflush(iop);
                if (iop->_flag & _IORW) {
                        iop->_cnt = 0;
                fflush(iop);
                if (iop->_flag & _IORW) {
                        iop->_cnt = 0;


@@ -44,5 +51,5 @@ fseek(iop, offset, ptrname)
                }
                p = lseek(fileno(iop), offset, ptrname);
        }
                }
                p = lseek(fileno(iop), offset, ptrname);
        }

-       return(p==-1? -1: 0);
+       return(p==-1?-1:0);

 }
 }