/* * 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. *//* * pANS stdio -- freopen */#include "iolib.h"/* * Open the named file with the given mode, using the given FILE * Legal modes are given below, `additional characters may follow these sequences': * r rb open to read * w wb open to write, truncating * a ab open to write positioned at eof, creating if non-existant * r+ r+b rb+ open to read and write, creating if non-existant * w+ w+b wb+ open to read and write, truncating * a+ a+b ab+ open to read and write, positioned at eof, creating if non-existant. */FILE *freopen(const char *name, const char *mode, FILE *f){ int m; if(f->state!=CLOSED){ fclose(f);/* premature; fall through and see what happens *//* f->state=OPEN; */ } m = *mode++; if(m == 0) return NULL; if(*mode == 'b') mode++; switch(m){ default: return NULL; case 'r': f->fd=open(name, (*mode == '+'? O_RDWR: O_RDONLY)); break; case 'w': f->fd=creat(name, 0666); /* implicitly O_WRONLY */ /* for O_RDWR, have to creat, close, open */ if(*mode == '+' && f->fd >= 0) { close(f->fd); f->fd=open(name, O_RDWR); } break; case 'a': f->fd=open(name, (*mode == '+'? O_RDWR: O_WRONLY)); if(f->fd<0) { f->fd=creat(name, 0666); /* for O_RDWR, have to creat, close, open */ if(*mode == '+' && f->fd >= 0) { close(f->fd); f->fd=open(name, O_RDWR); } } lseek(f->fd, 0L, 2); break; } if(f->fd==-1) return NULL; f->flags=(mode[0]=='a')? APPEND : 0; f->state=OPEN; f->buf=0; f->rp=0; f->wp=0; f->lp=0; return f;}
/*
* 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.
*/
/*
* pANS stdio -- freopen
*/
#include "iolib.h"
/*
* Open the named file with the given mode, using the given FILE
* Legal modes are given below, `additional characters may follow these sequences':
* r rb open to read
* w wb open to write, truncating
* a ab open to write positioned at eof, creating if non-existant
* r+ r+b rb+ open to read and write, creating if non-existant
* w+ w+b wb+ open to read and write, truncating
* a+ a+b ab+ open to read and write, positioned at eof, creating if non-existant.
*/
FILE *freopen(const char *name, const char *mode, FILE *f){
int m;
if(f->state!=CLOSED){
fclose(f);
/* premature; fall through and see what happens */
/* f->state=OPEN; */
}
m = *mode++;
if(m == 0)
return NULL;
if(*mode == 'b')
mode++;
switch(m){
default:
return NULL;
case 'r':
f->fd=open(name, (*mode == '+'? O_RDWR: O_RDONLY));
break;
case 'w':
f->fd=creat(name, 0666); /* implicitly O_WRONLY */
/* for O_RDWR, have to creat, close, open */
if(*mode == '+' && f->fd >= 0) {
close(f->fd);
f->fd=open(name, O_RDWR);
}
break;
case 'a':
f->fd=open(name, (*mode == '+'? O_RDWR: O_WRONLY));
if(f->fd<0) {
f->fd=creat(name, 0666);
/* for O_RDWR, have to creat, close, open */
if(*mode == '+' && f->fd >= 0) {
close(f->fd);
f->fd=open(name, O_RDWR);
}
}
lseek(f->fd, 0L, 2);
break;
}
if(f->fd==-1)
return NULL;
f->flags=(mode[0]=='a')? APPEND : 0;
f->state=OPEN;
f->buf=0;
f->rp=0;
f->wp=0;
f->lp=0;
return f;
}