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Example Code

Many times it helps to see an example of how to use a function. The following examples are ILE C programs that use typical UNIX functions and show the use of various functions. Some good examples for OS/400 PASE are in Chapter 10 of the Porting UNIX Applications Using iSeries PASE (SG24-5970-00) Redbook. (Note, however, that much of the Redbook has been superseded by standard documentation in the iSeries Information Center.) There are numerous examples of program and procedure calls between ILE and PASE.

The following examples are written in C language and compiled for Integrated Language Environment (ILE)

Multiprogramming

• Creating threads and getting return data
• Getting thread return data and writing trace data
• Mutex locking and unlocking
• spawn() and wait() to start a child process
• Client/Server use of semaphores and shared memory
• Client/Server use of OS/400 data queue objects

Network

• SMTP Mail send utility

Text Processing

• Getting and setting of an environment variable
• Use of iconv() functions to convert characters from one CCSID to another CCSID

Screen I/O

• Getting hidden typed input (for passwords)
• Dynamic Screen Manager (DSM) APIs for a text interface

Miscellaneous

• DLL functions - Dynamically loading libraries (service programs) and resolving function pointers
• Switching to a user ID similar to using setuid()
• Reading the system clock for microsecond-resolution wall-clock timing

API Implementation Examples

• alloca()
• bcmp()
• bcopy()
• bzero()
• ecvt()
• finite()
• getdtablesize()
• index()
• isnan()
• popen()
• pclose()
• random()
• rindex()
• srandom()
• syserrlist()
• _toupper()

These code samples that are furnished by IBM are to provide an illustration of concept. These examples have not been thoroughly tested under all conditions. IBM, therefore, cannot guarantee or imply reliability, serviceability, or function of these programs. All programs contained herein are provided to you "AS IS". THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE EXPRESSLY DISCLAIMED.