Performing file test operations in C

[akn846]

I need to write a C program which will test to see whether or not a file exists within a given directory or not.

I know how to do this in Unix shell script (Korn) but I would appreciate it if someone could tell me how I could do something similar in C?

Thanks

Andy

 

[Leibnitz]

#include <iostream.h>
#include <windows.h>
void main()
{
WIN32_FIND_DATA file;
HANDLE hFile;
if (( hFile = FindFirstFile( &quot;file_path&quot;,&file ))
== INVALID_HANDLE_VALUE )
{
cout<<&quot;Can't found this file in that directory !&quot;<<endl;
exit(0);
}
FindClose( hFile );
}

replace 'file_path' with the convenient file directory.

 

[lordblood]

Can try something like this.

#include <sys/types.h>
#include <sys/stat.h>

int FileExists(char *filename)
{
struct stat buf;

if( stat(filename, &buf) )
{
printf(&quot;File Does Not Exist!&quot;
return -1;
}

return 0; /*File Exists*/
}

see man pages for stat for details

 

[rwb1959]

Since stat() can fail for various reasons and will
return a &quot;-1&quot; on failure you probably want to do...

...
if( (stat(filename, &buf)) < 0 )
{
if( errno == ENOENT)
printf(&quot;File Does Not Exist!&quot;
else
printf(&quot;Error getting file stat&quot;
return -1;
}
...

Of course, it's probably better to use &quot;perror()&quot; to get the exact
system error message. In any case, the error codes would be listed
in the man pages...


ERRORS
EBADF filedes is bad.

ENOENT A component of the path file_name does not exist,
or the path is an empty string.

ENOTDIR
A component of the path is not a directory.

ELOOP Too many symbolic links encountered while travers­
ing the path.

EFAULT Bad address.

EACCES Permission denied.

ENOMEM Out of memory (i.e. kernel memory).

ENAMETOOLONG
File name too long.