PMEM2_CONFIG_SET_PROTECTION(3)

💖 PMEM2_CONFIG_SET_PROTECTION(3) 💖

okay bestie, welcome to the PMDK Programmer's Manual ✨ this one lives in libpmem2 and it's literally just about telling your memory mapping what it's allowed to do. protection flags, but make it fashion 💅

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🌸 NAME 🌸

pmem2_config_set_protection() — set a protection flags in pmem2_config structure.

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✨ SYNOPSIS ✨

#include <libpmem2.h>

struct pmem2_config;

#define PMEM2_PROT_EXEC     (1U << 29)
#define PMEM2_PROT_READ     (1U << 30)
#define PMEM2_PROT_WRITE    (1U << 31)
#define PMEM2_PROT_NONE     0

int pmem2_config_set_protection(struct pmem2_config *cfg,
        unsigned prot);

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🦋 DESCRIPTION 🦋

so the way that pmem2_config_set_protection() works is: it sets the protection flags that are gonna be used for memory mapping. your mapping's whole permission slip, basically 🎀

the default value sitting in the pmem2_config structure is PMEM2_PROT_READ | PMEM2_PROT_WRITE. and that prot argument? it's describing the desired memory protection of the mapping. key word: desired 🙈

⚠️ no cap, the memory protection cannot conflict with the file opening-mode. so don't come in here asking for write access when you opened the file read-only, bestie, it's not gonna work.

also, config should already be initialized before you call this. not me forgetting to init it 💀 go peek at pmem2_config_new(3) for the details on that.

so the value you pass is either PROT_NONE or the bitwise OR of one or more of these iconic little flags:

• PMEM2_PROT_EXEC — Pages may be executed.
• PMEM2_PROT_READ — Pages may be read.
• PMEM2_PROT_WRITE — Pages may be written.
• PMEM2_PROT_NONE — Pages may not be accessed. (yeah, zero access. the silent treatment 💀)

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🔥 RETURN VALUE 🔥

pmem2_config_set_protection() returns 0 on success, or a negative error code if it fails. that's it, that's the tea ☕

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💀 ERRORS 💀

pmem2_config_set_protection() can fail with the following errors:

• PMEM2_E_INVALID_PROT_FLAG — some or all of the provided flags are not valid. like, you handed it a flag that does not exist. it's giving made-up flag energy, and the function is NOT having it 😭

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👑 SEE ALSO 👑

libpmem2(7), pmem2_config_new(3), pmem2_map_new(3) and https://pmem.io 🌈

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and that's the whole page, babe 🫶 go forth and protect your mappings responsibly 💖

PMDK — 2025-07-24 ⭐ mwah, slay, periodt ✨