Skip to content

brk

Implemented in Antinomie 0.7.0 · Syscall list

long brk(unsigned long brk);
Number (x86-64) 12
ABI common
Kernel entry point sys_brk

This is the raw kernel prototype from the pinned Linux 6.12.94 schema, not the libc wrapper.

Sets the end of the data segment (the program break), which is how the classic heap grows or shrinks.

Name Type Meaning
brk (arg0) unsigned long Requested new program break address.

On success: the new program break.

In an Antinomie trace the Return column and the ret filter field show the raw kernel return value. On failure that is the negative errno, for example -2 for ENOENT, not the -1 plus errno that the libc wrapper gives. syscall.errno holds the positive errno and syscall.success is false.

Raw return Name Meaning
-12 ENOMEM The kernel is out of memory.

brk(2) on man7.org

Coverage mark: Implemented. All arguments are plain values, recorded as the raw argument words at entry. There is no pointee to copy and no known gap.

Every call is recorded as an Entry record (the six argument words and the pointees copied at entry) and an Exit record (the return value and the pointees copied at exit).

Argument When How Recorded field key Condition
brk (arg0) Entry raw scalar word args.0, args.brk
  • Result: ret, syscall.errno, syscall.success, syscall.duration_ns.
  • Argument words: args.brk (arg0); args.0 to args.5 by position.

See Syscall Trace filter for the full syntax.

For what the capture statuses mean, see Capture statuses. For what is never recorded, see Known gaps.