getcwd(3c) - osol9

1getcwd(3C)               Standard C Library Functions               getcwd(3C)
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NAME

6       getcwd - get pathname of current working directory
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SYNOPSIS

9       #include <unistd.h>
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11       char *getcwd(char *buf, size_t size);
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DESCRIPTION

15       The  getcwd() function places an absolute pathname of the current work‐
16       ing directory in the array pointed to by  buf,  and  returns  buf.  The
17       pathname  copied  to the array contains no components that are symbolic
18       links. The size argument is the size in bytes of  the  character  array
19       pointed  to  by buf and must be at least one greater than the length of
20       the pathname to be returned.
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23       If buf is not a null pointer, the  pathname  is  stored  in  the  space
24       pointed to by buf.
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27       If  buf  is  a null pointer, getcwd() obtains size bytes of space using
28       malloc(3C). The pointer returned by getcwd() can be used as  the  argu‐
29       ment in a subsequent call to free().
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RETURN VALUES

32       Upon  successful  completion, getcwd() returns the buf argument. If buf
33       is an invalid destination buffer address, NULL is returned and errno is
34       set  to  EFAULT. Otherwise, a null pointer is returned and errno is set
35       to indicate the error.
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ERRORS

38       The getcwd() function will fail if:
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40       EFAULT    The buf argument is an invalid destination buffer address.
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43       EINVAL    The size argument is equal to 0.
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46       ERANGE    The size argument is greater than 0 and less than the  length
47                 of the pathname plus 1.
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51       The getcwd() function may fail if:
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53       EACCES    A parent directory cannot be read to get its name.
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56       ENOMEM    Insufficient storage space is available.
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EXAMPLES

60       Example 1 Determine the absolute pathname of the current working direc‐
61       tory.
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64       The following example returns a pointer to  an  array  that  holds  the
65       absolute  pathname  of  the  current  working directory. The pointer is
66       returned in the ptr variable, which points to the buf array  where  the
67       pathname is stored.
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70         #include <stdlib.h>
71         #include <unistd.h>
72         ...
73         long size;
74         char *buf;
75         char *ptr;
76         size = pathconf(".", _PC_PATH_MAX);
77         if ((buf = (char *)malloc((size_t)size)) != NULL)
78                ptr = getcwd(buf, (size_t)size);
79         ...
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82       Example 2 Print the current working directory.
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85       The following example prints the current working directory.
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88         #include <unistd.h>
89         #include <stdio.h>
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91         main()
92         {
93             char *cwd;
94             if ((cwd = getcwd(NULL, 64)) == NULL) {
95                 perror("pwd");
96                 exit(2);
97             }
98             (void)printf("%s\n", cwd);
99             free(cwd); /* free memory allocated by getcwd() */
100             return(0);
101         }
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USAGE

105       Applications  should  exercise  care when using chdir(2) in conjunction
106       with getcwd(). The current working directory is global to  all  threads
107       within  a  process. If more than one thread calls chdir() to change the
108       working directory, a subsequent call to getcwd()  could  produce  unex‐
109       pected results.
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ATTRIBUTES

112       See attributes(5) for descriptions of the following attributes:
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117       ┌─────────────────────────────┬─────────────────────────────┐
118       │      ATTRIBUTE TYPE         │      ATTRIBUTE VALUE        │
119       ├─────────────────────────────┼─────────────────────────────┤
120       │Interface Stability          │Standard                     │
121       ├─────────────────────────────┼─────────────────────────────┤
122       │MT-Level                     │MT-Safe                      │
123       └─────────────────────────────┴─────────────────────────────┘
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