1GETCWD(3P) POSIX Programmer's Manual GETCWD(3P)
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6 This manual page is part of the POSIX Programmer's Manual. The Linux
7 implementation of this interface may differ (consult the corresponding
8 Linux manual page for details of Linux behavior), or the interface may
9 not be implemented on Linux.
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13 getcwd — get the pathname of the current working directory
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16 #include <unistd.h>
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18 char *getcwd(char *buf, size_t size);
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21 The getcwd() function shall place an absolute pathname of the current
22 working directory in the array pointed to by buf, and return buf. The
23 pathname shall contain no components that are dot or dot-dot, or are
24 symbolic links.
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26 If there are multiple pathnames that getcwd() could place in the array
27 pointed to by buf, one beginning with a single <slash> character and
28 one or more beginning with two <slash> characters, then getcwd() shall
29 place the pathname beginning with a single <slash> character in the
30 array. The pathname shall not contain any unnecessary <slash> charac‐
31 ters after the leading one or two <slash> characters.
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33 The size argument is the size in bytes of the character array pointed
34 to by the buf argument. If buf is a null pointer, the behavior of
35 getcwd() is unspecified.
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38 Upon successful completion, getcwd() shall return the buf argument.
39 Otherwise, getcwd() shall return a null pointer and set errno to indi‐
40 cate the error. The contents of the array pointed to by buf are then
41 undefined.
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44 The getcwd() function shall fail if:
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46 EINVAL The size argument is 0.
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48 ERANGE The size argument is greater than 0, but is smaller than the
49 length of the string +1.
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51 The getcwd() function may fail if:
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53 EACCES Search permission was denied for the current directory, or read
54 or search permission was denied for a directory above the cur‐
55 rent directory in the file hierarchy.
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57 ENOMEM Insufficient storage space is available.
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59 The following sections are informative.
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62 The following example uses {PATH_MAX} as the initial buffer size
63 (unless it is indeterminate or very large), and calls getcwd() with
64 progressively larger buffers until it does not give an [ERANGE] error.
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66 #include <stdlib.h>
67 #include <errno.h>
68 #include <unistd.h>
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70 ...
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72 long path_max;
73 size_t size;
74 char *buf;
75 char *ptr;
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77 path_max = pathconf(".", _PC_PATH_MAX);
78 if (path_max == -1)
79 size = 1024;
80 else if (path_max > 10240)
81 size = 10240;
82 else
83 size = path_max;
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85 for (buf = ptr