getcwd,  get_current_dir_name, getwd - Get current working
       directory

SYNOPSIS

       #include <unistd.h>

       char *getcwd(char *buf, size_t size);
       char *get_current_dir_name(void);
       char *getwd(char *buf);

DESCRIPTION

       The getcwd() function copies the absolute pathname of  the
       current  working directory to the array pointed to by buf,
       which is of length size.

       If the current absolute path name would require  a  buffer
       longer  than size elements, NULL is returned, and errno is
       set to ERANGE; an application should check for this error,
       and allocate a larger buffer if necessary.

       As  an  extension  to the POSIX.1 standard, getcwd() allo­
       cates the buffer dynamically using malloc() if buf is NULL
       on  call.   In  this  case,  the  allocated buffer has the
       length size unless size is zero, when buf is allocated  as
       big as necessary.  It is possible (and, indeed, advisable)
       to free() the buffers if they have been obtained this way.

       get_current_dir_name,   which   is   only   prototyped  if
       _GNU_SOURCE is defined, will malloc(3) an array big enough
       to  hold  the  current directory name.  If the environment
       variable PWD is set, and its value is correct,  then  that
       value will be returned.

       getwd,   which   is  only  prototyped  if  _BSD_SOURCE  or
       _XOPEN_SOURCE_EXTENDED is defined, will not malloc(3)  any
       memory.  The  buf argument should be a pointer to an array
       at least PATH_MAX bytes long.  getwd does only return  the
       first PATH_MAX bytes of the actual pathname.

RETURN VALUE

       NULL  on failure (for example, if the current directory is
       not readable), with errno set accordingly, and buf on suc­
       cess.

CONFORMING TO

       POSIX.1

SEE ALSO

       chdir(2), free(3), malloc(3).