.TH "libnvmf_registry_device_for_each" 9 "libnvmf_registry_device_for_each" "October 2026" "libnvme API manual" LINUX
.SH NAME
libnvmf_registry_device_for_each \- Iterate over live controller registry entries
.SH SYNOPSIS
.B "int" libnvmf_registry_device_for_each
.BI "(struct libnvme_global_ctx *ctx "  ","
.BI "int (*callback)(const char *device, void *user_data) "  ","
.BI "void *user_data "  ");"
.SH ARGUMENTS
.IP "ctx" 12
libnvme global context; must not be NULL
.IP "callback" 12
Callback invoked for each live entry
.IP "user_data" 12
User data passed to \fIcallback\fP
.SH "DESCRIPTION"
Scans the registry directory and invokes \fIcallback\fP for each entry whose
corresponding /dev/nvmeN device node exists.  Stale entries left behind
after a controller is removed are silently skipped.  The existence check is
advisory: a device may be removed between the check and callback invocation;
callers should handle ENOENT gracefully.
.SH "RETURN"
0 on success, negative errno if the registry directory cannot be
opened.  Returns 0 when the directory does not exist (nothing registered).