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NAME |LIBRARY |SYNOPSIS |DESCRIPTION |RETURN VALUE |ERRORS |ATTRIBUTES |VERSIONS |VERSIONS |STANDARDS |HISTORY |NOTES |BUGS |SEE ALSO |COLOPHON | |
getcwd(3) Library Functions Manualgetcwd(3)getcwd, getwd, get_current_dir_name - get current working directory
Standard C library (libc,-lc)
#include <unistd.h>char *getcwd(size_t size;charbuf[size], size_tsize);char *get_current_dir_name(void);[[deprecated]] char *getwd(charbuf[PATH_MAX]); Feature Test Macro Requirements for glibc (seefeature_test_macros(7)):get_current_dir_name(): _GNU_SOURCEgetwd(): Since glibc 2.12: (_XOPEN_SOURCE >= 500) && ! (_POSIX_C_SOURCE >= 200809L) || /* glibc >= 2.19: */ _DEFAULT_SOURCE || /* glibc <= 2.19: */ _BSD_SOURCE Before glibc 2.12: _BSD_SOURCE || _XOPEN_SOURCE >= 500
These functions return a null-terminated string containing an absolute pathname that is the current working directory of the calling process. The pathname is returned as the function result and via the argumentbuf, if present. Thegetcwd() function copies an absolute pathname of the current working directory to the array pointed to bybuf, which is of lengthsize. If the length of the absolute pathname of the current working directory, including the terminating null byte, exceedssize bytes, NULL is returned, anderrno is set toERANGE; an application should check for this error, and allocate a larger buffer if necessary. As an extension to the POSIX.1-2001 standard, glibc'sgetcwd() allocates the buffer dynamically usingmalloc(3) ifbuf is NULL. In this case, the allocated buffer has the lengthsize unlesssize is zero, whenbuf is allocated as big as necessary. The caller shouldfree(3) the returned buffer.get_current_dir_name() willmalloc(3) an array big enough to hold the absolute pathname of the current working directory. If the environment variablePWDis set, and its value is correct, then that value will be returned. The caller shouldfree(3) the returned buffer.getwd() does notmalloc(3) any memory. Thebuf argument should be a pointer to an array at leastPATH_MAXbytes long. If the length of the absolute pathname of the current working directory, including the terminating null byte, exceedsPATH_MAXbytes, NULL is returned, anderrno is set toENAMETOOLONG. (Note that on some systems,PATH_MAXmay not be a compile-time constant; furthermore, its value may depend on the filesystem, seepathconf(3).) For portability and security reasons, use ofgetwd() is deprecated.
On success, these functions return a pointer to a string containing the pathname of the current working directory. In the case ofgetcwd() andgetwd() this is the same value asbuf. On failure, these functions return NULL, anderrno is set to indicate the error. The contents of the array pointed to bybuf are undefined on error.
EACCESPermission to read or search a component of the filename was denied.EFAULTbuf points to a bad address.EINVALThesize argument is zero andbuf is not a null pointer.EINVAL getwd():buf is NULL.ENAMETOOLONGgetwd(): The size of the null-terminated absolute pathname string exceedsPATH_MAXbytes.ENOENTThe current working directory has been unlinked.ENOMEMOut of memory.ERANGEThesize argument is less than the length of the absolute pathname of the working directory, including the terminating null byte. You need to allocate a bigger array and try again.
For an explanation of the terms used in this section, seeattributes(7). ┌──────────────────────────────────┬───────────────┬─────────────┐ │Interface│Attribute│Value│ ├──────────────────────────────────┼───────────────┼─────────────┤ │getcwd(),getwd() │ Thread safety │ MT-Safe │ ├──────────────────────────────────┼───────────────┼─────────────┤ │get_current_dir_name() │ Thread safety │ MT-Safe env │ └──────────────────────────────────┴───────────────┴─────────────┘
POSIX.1-2001 leaves the behavior ofgetcwd() unspecified ifbuf is NULL. POSIX.1-2001 does not define any errors forgetwd().
C library/kernel differences On Linux, the kernel provides agetcwd() system call, which the functions described in this page will use if possible. The system call takes the same arguments as the library function of the same name, but is limited to returning at mostPATH_MAXbytes. (Before Linux 3.12, the limit on the size of the returned pathname was the system page size. On many architectures,PATH_MAXand the system page size are both 4096 bytes, but a few architectures have a larger page size.) If the length of the pathname of the current working directory exceeds this limit, then the system call fails with the errorENAMETOOLONG. In this case, the library functions fall back to a (slower) alternative implementation that returns the full pathname. Following a change in Linux 2.6.36, the pathname returned by thegetcwd() system call will be prefixed with the string "(unreachable)" if the current directory is not below the root directory of the current process (e.g., because the process set a new filesystem root usingchroot(2) without changing its current directory into the new root). Such behavior can also be caused by an unprivileged user by changing the current directory into another mount namespace. When dealing with pathnames from untrusted sources, callers of the functions described in this page (before glibc 2.27) or the rawgetcwd() system call should consider checking whether the returned pathname starts with '/' or '(' to avoid misinterpreting an unreachable path as a relative pathname.getcwd() POSIX.1-2008.get_current_dir_name() GNU.getwd() None.
getcwd() POSIX.1-2001.getwd() POSIX.1-2001, but marked LEGACY. Removed in POSIX.1-2008. Usegetcwd() instead. Under Linux, these functions make use of thegetcwd() system call (available since Linux 2.1.92). On older systems they would query/proc/self/cwd. If both system call and proc filesystem are missing, a generic implementation is called. Only in that case can these calls fail under Linux withEACCES.
These functions are often used to save the location of the current working directory for the purpose of returning to it later. Opening the current directory (".") and callingfchdir(2) to return is usually a faster and more reliable alternative when sufficiently many file descriptors are available, especially on platforms other than Linux.Since the Linux 2.6.36 change that added "(unreachable)" in the circumstances described above, the glibc implementation ofgetcwd() has failed to conform to POSIX and returned a relative pathname when the API contract requires an absolute pathname. With glibc 2.27 onwards this is corrected; callinggetcwd() from such a pathname will now result in failure withENOENT.
pwd(1),chdir(2),fchdir(2),open(2),unlink(2),free(3),malloc(3)
This page is part of theman-pages (Linux kernel and C library user-space interface documentation) project. Information about the project can be found at ⟨https://www.kernel.org/doc/man-pages/⟩. If you have a bug report for this manual page, see ⟨https://git.kernel.org/pub/scm/docs/man-pages/man-pages.git/tree/CONTRIBUTING⟩. This page was obtained from the tarball man-pages-6.15.tar.gz fetched from ⟨https://mirrors.edge.kernel.org/pub/linux/docs/man-pages/⟩ on 2025-08-11. If you discover any rendering problems in this HTML version of the page, or you believe there is a better or more up- to-date source for the page, or you have corrections or improvements to the information in this COLOPHON (which isnot part of the original manual page), send a mail to man-pages@man7.orgLinux man-pages 6.15 2025-06-28getcwd(3)Pages that refer to this page:pwd(1), chdir(2), syscalls(2), realpath(3), core(5)
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