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umask(2) [opendarwin man page]

UMASK(2)						      BSD System Calls Manual							  UMASK(2)

umask -- set file creation mode mask SYNOPSIS
#include <sys/types.h> #include <sys/stat.h> mode_t umask(mode_t numask); DESCRIPTION
The umask() routine sets the process's file mode creation mask to numask and returns the previous value of the mask. The 9 low-order access permission bits of numask are used by system calls, including open(2), mkdir(2), mkfifo(2) and mknod(2) to turn off corresponding bits requested in file mode. (See chmod(2)). This clearing allows each user to restrict the default access to his files. The default mask value is S_IWGRP|S_IWOTH (022, write access for the owner only). Child processes inherit the mask of the calling process. RETURN VALUES
The previous value of the file mode mask is returned by the call. ERRORS
The umask() function is always successful. SEE ALSO
chmod(2), mkdir(2), mkfifo(2), mknod(2), open(2) STANDARDS
The umask() function call is expected to conform to IEEE Std 1003.1-1988 (``POSIX.1''). 4th Berkeley Distribution June 4, 1993 4th Berkeley Distribution

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umask(2)							System Calls Manual							  umask(2)

umask - Sets and gets the value of the file creation mask SYNOPSIS
#include <sys/types.h> #include <sys/stat.h> mode_t umask ( mode_t cmask ); STANDARDS
Interfaces documented on this reference page conform to industry standards as follows: umask(): POSIX.1, XPG4, XPG4-UNIX Refer to the standards(5) reference page for more information about industry standards and associated tags. PARAMETERS
Specifies the value of the file mode creation mask. DESCRIPTION
The umask() function sets the file mode creation mask of the process to the value of the cmask parameter and returns the previous value of the mask. The cmask parameter is constructed by logically ORing file permission bits defined in the sys/mode.h header file. Whenever a file is created (by the open(), mkdir(), or mknod() function), all file permission bits set in the file mode creation mask are cleared in the mode of the created file. This clearing lets users restrict the default access to their files. The mask is inherited by child processes. RETURN VALUES
Upon successful completion, the previous value of the file mode creation mask is returned. RELATED INFORMATION
Commands: chmod(1), mkdir(1), Bourne shell sh(1b), POSIX shell sh(1p), umask(1) Functions: chmod(2), mkdir(2), mknod(2), open(2), stat(2) Standards: standards(5) delim off umask(2)
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