See also: Kernel Index, Memory, System Services
This directory contains lightweight libc-style helpers used inside the kernel without relying on the host C library.
Components
String Library
string.c / string.h — Basic string operations:
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strcpy(),strncpy(),strcmp(),strncmp() -
strlen(),strcat(),strchr(),strrchr() -
strstr(),strtok(),memcpy(),memset(),memmove()
Standard I/O
stdio.c / stdio.h — Kernel-side formatted output:
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printf()— Print formatted string to TTY -
logfmt()— Formatted logging with severity levels (LOG_INFO, LOG_ERROR, etc.) -
sprintf()— Format string to buffer -
puts(),putchar()
Character Types
ctype.c / ctype.h — Character classification:
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isalpha(),isdigit(),isalnum(),isspace() -
toupper(),tolower(),isprint()
Utility Headers
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binary.h— Bit manipulation macros -
arrays.h— Array utility macros -
minmax.h— MIN/MAX macros
Key Design
These utilities are designed to be minimal and deterministic for kernel-level use. They do not depend on userspace libc.
Typical Work in This Area
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Add missing utility routines needed by kernel modules
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Optimize frequently used primitives
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Keep behavior stable and minimal for kernel constraints