getcwd()
Get the name of the current working directory
Synopsis:
#include <unistd.h>
char* getcwd( char* buffer,
size_t size );
Arguments:
- buffer
- NULL, or a pointer to a buffer where the function can store the directory name.
- size
- The size of the buffer, in bytes.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The getcwd() function returns the name of the current working directory. buffer is a pointer to a buffer of at least size bytes where the NUL-terminated name of the current working directory will be placed.
The maximum size that might be required for buffer is PATH_MAX bytes. See <limits.h>.
getcwd( NULL, 0).
The QNX OS version (like many others) allocates a buffer for the name
of the directory; it's up to your application to free the buffer when you
no longer need it.
Returns:
The address of the string containing the name of the current working directory, or NULL if an error occurred (errno is set).
Errors:
- EINVAL
- The argument size is negative or 0.
- ELOOP
- Too many levels of symbolic links.
- ENOSYS
- The getcwd() function isn't implemented for the filesystem specified in the current working directory.
- ERANGE
- The buffer is too small (as specified by size) to contain the name of the current working directory.
Examples:
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <limits.h>
int main( void )
{
char* cwd;
char buff[PATH_MAX];
cwd = getcwd( buff, PATH_MAX );
if( cwd != NULL ) {
printf( "My working directory is %s.\n", cwd );
}
return EXIT_SUCCESS;
}
produces the output:
My working directory is /home/bill.
Classification:
| Safety: | |
|---|---|
| Cancellation point | Yes |
| Signal handler | No |
| Thread | Yes |
Caveats:
There is only one current working directory per process. In a multithreaded application, any thread calling chdir() will change the current working directory for all threads in that process.