usr/src/libI77/endfile.c

#include "fio.h"
static alist *ax;
f_end(a) alist *a;
{
        unit *b;
        if(a->aunit>=MXUNIT || a->aunit<0) err(a->aerr,101,"endfile");
        b = &units[a->aunit];
        if(b->ufd==NULL) return(0);
        b->uend=1;
        if( b->useek==0) return(0);
        ax=a;
        if(b->uwrt) nowreading(b);
        return(t_runc(b));
}
t_runc(b) unit *b;
{
        char buf[128],nm[16];
        FILE *tmp;
        int n,m;
        long loc,len;
        if(b->url) return(0);   /*don't truncate direct files*/
        loc=ftell(b->ufd);
        fseek(b->ufd,0L,2);
        len=ftell(b->ufd);
        if(loc==len || b->useek==0 || b->ufnm==NULL) return(0);
        strcpy(nm,"tmp.FXXXXXX");
        if(b->uwrt) nowreading(b);
        mktemp(nm);
        tmp=fopen(nm,"w");
        fseek(b->ufd,0L,0);
        for(;loc>0;)
        {
                n=fread(buf,1,loc>128?128:(int)loc,b->ufd);
                if(n>loc) n=loc;
                loc -= n;
                fwrite(buf,1,n,tmp);
        }
        fflush(tmp);
        for(n=0;n<10;n++)
        {
                if((m=fork())==-1) continue;
                else if(m==0)
                {
                        execl("/bin/cp","cp",nm,b->ufnm,0);
                        execl("/usr/bin/cp","cp",nm,b->ufnm,0);
                        fprintf(stdout,"no cp\n");
                        exit(1);
                }
                wait(&m);
                if(m!=0) err(ax->aerr,111,"endfile");
                fclose(tmp);
                unlink(nm);
                return(0);
        }
        err(ax->aerr,111,"endfile");
}