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== Syscall Mechanism ==
Every platform has a different syscall mechanism. Each mechanism is documented in the ABI standards for that platform, and a summary of various platforms is contained in the manpage for syscall(2) (run the command <code>man 2 syscall</code> to see this).
To invoke a syscall in your own code, load the syscall number and arguments into the appropriate registers, and then invoke the architecture-specific syscall mechanism, using the details below:
=== Documentation ===
A list of syscalls can be found in the manpage for <code>syscalls(2)</code> (note: this is different from the manpage for <code>syscall(2)</code> which is a generic syscall wrapper).View this with the command <code>man 2 syscalls</code>
Documentation for the C wrappers for most syscalls can be found in the manpage for that wrapper, usually in section 2 of the manual (e.g., <code>write(2)</code>, which is accessed using the command <code>man 2 write</code>).
== Using the syscall number macro definitions in asm code ==
The syscall macros can be used in an assembly program if that program is processed by the C preprocessor (cpp). The extension <code>.S</code> (uppercase instead of lowercase) is used to designate an assembler source file that must be processed by cpp.
