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loop
Post 8760 by rwb1959 on Wednesday 17th of October 2001 11:54:59 AM
10-17-2001
Well... I know Neo is going to bust my chops for this
but you did try somthing and you need a little
direction so here goes...
OK. The first thing you should do in all shell scripts is to
set up the execution environment. You do this by inserting
the following line as the very first line in your script
(without the comments)...
#!/bin/sh <- Bourne Shell (normally)
...or
#!/bin/ksh <- Korn Shell
...or
#!/bin/csh <- C Shell
...remember that $* expands to ALL the positional parameters.
You need to read each one into a variable...
for prog in $*
do
... now, each time through the loop, $prog contains the next
positional parameter. Next, you want to check $prog for
"ordinary file" AND "executable file"...
if [ -f $prog -a -x $prog ]
then
...
else
...
fi
...then end your "do/done" loop and exit
done
exit 0
...just FYI, it's good programming practice to return some
sort of value (0 = AOK, 255 = Error) although this is a personal
preference.
You can then run this script in the background...
myscript /bin/ls /usr/bin/stat /bin/df ./myprog &
...you get the picture.
but you did try somthing and you need a little
direction so here goes...
OK. The first thing you should do in all shell scripts is to
set up the execution environment. You do this by inserting
the following line as the very first line in your script
(without the comments)...
#!/bin/sh <- Bourne Shell (normally)
...or
#!/bin/ksh <- Korn Shell
...or
#!/bin/csh <- C Shell
...remember that $* expands to ALL the positional parameters.
You need to read each one into a variable...
for prog in $*
do
... now, each time through the loop, $prog contains the next
positional parameter. Next, you want to check $prog for
"ordinary file" AND "executable file"...
if [ -f $prog -a -x $prog ]
then
...
else
...
fi
...then end your "do/done" loop and exit
done
exit 0
...just FYI, it's good programming practice to return some
sort of value (0 = AOK, 255 = Error) although this is a personal
preference.
You can then run this script in the background...
myscript /bin/ls /usr/bin/stat /bin/df ./myprog &
...you get the picture.
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LEARN ABOUT CENTOS
pcp.conf
PCP.CONF(5) File Formats Manual PCP.CONF(5) NAME
pcp.conf - the Performance Co-Pilot configuration and environment file SYNOPSIS
/etc/pcp.conf DESCRIPTION
When using Performance Co-Pilot (PCP) tools and utilities and when calling PCP library functions, a standard set of environment variables are defined in /etc/pcp.conf. These variables are generally used to specify the location of various PCP pieces in the file system and may be loaded into shell scripts by sourcing the /etc/pcp.env(5) shell script and queried by C/C++ programs using the pmGetConfig(3) library function. If a variable is already defined in the environment, the values in pcp.conf do not override those values, i.e. the values in pcp.conf serve as installation defaults only. Both the pcp.env and pcp.conf files are expected to be found in /etc by default. If required, the pcp.conf file may be relocated and PCP_CONF set in the environment to specify the full path to the new location. The pcp.env file can not be relocated (this is the only hard coded path required by PCP). The syntax rules for pcp.conf are as follows : 1. the general syntax is PCP_VARIABLE_NAME=variable value to end of line 2. lines that begin with # and all blank lines are ignored. 3. all variables must be prefixed with PCP_. This is a security issue - variables that do not have this prefix will be silently ignored. 4. there should be no space between the variable name and the literal = and no space between the = and the variable value (unless the value actually starts with a space). This is required because the pcp.conf file may be sourced directly by Makefiles as well as inter- preted by the pcp.env script and the pmGetConfig function. 5. variable values may contain spaces and should not be quoted. The pcp.env script automatically quotes all variable values from the character immediately following the = through to the end of the line. For further details and an explanation of the use of each variable, see the comments in the /etc/pcp.conf file itself. ENVIRONMENT
The PCP_CONF environment variable specifies an alternative path to the pcp.conf file. SEE ALSO
PCPIntro(1), PCPIntro(3), PMAPI(3), pmGetConfig(3) and pcp.env(5). Performance Co-Pilot PCP PCP.CONF(5)