April 1, 1981
The jdnames pur:H and CMSIIB are used for and SYSLIB data
sets. PUN:H output is nroduced when you use the option of the command. The default file definition for CMSLIB is the macro libLaLV :MSLIB MACLIB, but you must still issue the command if you want to use it.
Executing Programs AfteL you have assembled or compiled a source proqram you can execute
the files that were produced by the assembly or You may not, however, be able to execute all your as programs directly in are a of execution-time restrictions placed on your
virtual machine by VM/370. You cannot execute a program that uses: • M 'II tit ask in cr • More than one partition • Teleprocessinq • ISAM macros to read or write files
The is only a partial list, representing those restrictions with
which you miqht be concerned. For a complete list of restrictions, see
the ggngrat i2ll EXECUTING TErT FILES files, in CMS, are relocatable, and can be executed simply by loadinq them into virtual storage with the LOAD command and using the command to beqin execution. For example, if you have assembled a proqram named CPEATE, you have a file named CREATE TEXT. You can
issue the command:
load create which loads the relocatable object file into storage, and then, to
execute it, you can issue the START command: start In the case of a simple program, as in the above example, you can
load and beqin execution with a single command line, using the START option of the LOAD command:
load CLeate (start When you issue the START command or LOAD command with the START
option, control is passed to the first entry point in your program. If
you have than one entry point and you want to begin execution at an entry point other than the first, you can specify the alternate entry
point or CSECT name on the START command:
start create2 When yoa issue the LOAD command specifying the filename of a TEXT file, CMS searches all of your accessed disks for the specified file.
If your proqram expects a parameter list to be passed (via register
1), you can specify the arguments on the START command line. If you enteL aLquments, then you must specify the entry point:
start * name1
144 IBM VM/370 CMS User's Guide

April 1, 1981 When Y01 specify the entry point as an asterisk (*) it indicates that you want to use the default entry point. You can issue the FILEDEF command to define input and output files any time before you beqin program execution. You can issue all your file
definitions before loading any TEXT files, or issue them during the
loadinq pro=ess. You can find out what file definitions are currently
in effe=t bv issuinq the command with no operands: file1ef You can also use the FILEDEF operand of the QUEPY command. TEXT LIBRARIES (TXTLIBS) You may want to keep your TEXT files in text libraries, that have a filetype of TXTLlB. Like MACLIBs, TXTLlBs have a directory and members. TXTLIBs are created and modified by the TXTLIB command, which has
functions similar to the command: • The GEN function creates the TXTLIB. • The function adds members to the TIrLIB. • The DEL function deletes members and compresses the TITLIB. • The function lists members.
There is no REn function; you must use a DEL followed by an ADD to
replace an existinq member. The eMS commands that recognize as
special filetvpes also recognize TITLIBs, and allow you to display,
print, punch TXTLIB members.
The TXTLIB command reads the object files as it writes them into the
library, and creates a directory entry for each entry point or CSECT name. If you have a TEXT file named which has a single routine named BEGIN, and create the TXTLIB named TESTLlB as follows:
txtlib qen test lib myprog TESTLlB contains no entry for the name you must specify the membernime BEGIN to reference this TITLIB member.
When you want to load members of TXTtlBs into storage to execute them
(;ust as yoa execute TEXT files), you must issue the GLOBAL command to
identify the TXTLlB: txtlib testlib load beqin {start When vou specify more than one TXTLlB on the GLOBAL command line, the
order of search is established for the TITLlBs. However, if the AUTO option is in effect (it is the default), searches for TEXT files
before searchinq active TXTLIEs. When the command processes a rEXT file, it writes an tDT
(loader terminate) card at the end of the TEXT file, so that when a load
request is issued for a TXTLIB member, loading terminates at the end of
the member. If you add as linkage editor control statements to the TEXT file fusinq the editor) before you issue the TITLlB command to add
the file to a TXTLlB, the control statements are processed as follows:
section 8. Developing os Proqrams Under CMS 145