creat
Creates a new file or overwrites an existing one.
Defined in header <sys/stat.h>
Syntax
#include <sys\stat.h>
int creat(const char *path, intamode);Portability
| DOS | UNIX | Windows | ANSI C | C++ only |
|---|---|---|---|---|
| ■ | ■ | ■ |
Remarks
creat creates a new file or prepares to rewrite an existing file given by path, amode applies only to newly created files.
A file created with creat is always created in the translation mode specified by the global variable _fmode (O_TEXT or O_BINARY).
If the file exists and the write attribute is set, creat truncates the file to a length of 0 bytes, leaving the file attributes unchanged. If the existing file has the read-only attribute set, the creat call fails and the file remains unchanged.
The creat call examines only the S_IWRITE bit of the access-mode word amode. If that bit is 1, the file can be is written to. If the bit is 0, the file is marked as read-only. All other DOS attributes are set to 0.
amode can be one of the following (defined in sysXstat.h):
| Value of amode | Access permission |
| SJWRITE | Permission to write |
| SJREAD | Permission to read |
| S IREADIS IWRITE | Permission to read and write |
In DOS, write permission implies read permission.
Return value
Upon successful completion, creat returns the new file handle, a non-negative integer; otherwise, it returns -1.
In the event of error, the global variable errno is set to one of the following:
ENOENT Path or file name not found EMFILE Too many open files EACCES Permission denied
See also
Example
#include <sys\stat.h>
#include <process.h>
#include <string.h>
#include <stdio.h>
#include <fcntl.h>
#include <errno.h>
#include <io.h>
int main (void)
{
int handle;
char buf [1 : '01234567S
/* create a binary file for reading and writing */
if ((handle = _creat("DUMMY.FIL", 0)) < 0) {
switch (errno) {
case ENOENT: printf ("Error: Path or file not found. \n"
break;
case EMFILE: printf ("Error: Too many open files.\n");
break;
case EACCES: printf ("Error: Permission denied.\n");
break;
default: printf ("Error creating file.\n");
break;
}
exit(l);
}
/* write a string and NULL terminator into the file */
write (handle, buf, strlen(buf)+l);
/* close the file */
close (handle);
return 0;Differences from modern implementations
Nothing recorded yet.
Modern references
These are search links, not yet checked by hand.
Stable link: /3.1/sys/stat.h/creat/
· short form /3.1/creat/