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The Open Group Base Specification Issue 6 [Open Group 2004] does not specify the permissions the file is created with, so these are implementation-defined. However, Issue 7 IEEE Std 1003.1, 2013 Edition [IEEE Std 1003.1:2013] specifies them as S_IRUSR|S_IWUSR (0600).
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| [HP 2003] | |
| [IEEE Std 1003.1:2013] | XSH, System Interfaces: openXSH, System Interfaces: mkdopen, mksopen |
| [ISO/IEC 9899:2011] | Subclause K.3.5.1.2, "The tmpnam_s Function"Subclause 7.21.4.4, "The tmpnam Function |
| [Kennaway 2000] | |
| [Open Group 2004] | open() |
| [Seacord 2013] | Chapter 3, "Pointer Subterfuge" Chapter 8, "File I/O" |
| [Viega 2003] | Section 2.1, "Creating Files for Temporary Use" |
| [Wheeler 2003] | Chapter 7, "Structure Program Internals and Approach" |
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