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Function into a condition ?

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    #1  
Old 03-14-2013
amazigh42 amazigh42 is offline
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Function into a condition ?

Hello,

How can i put a function into a condition ?
g1 is my function
I tested this in vain


Code:
if [ g1 $1 $2 $3 -ne 0 ];then


Code:
if [ $(g1 $1 $2 $3) -ne 0 ];then

Thanks for yours suggestions
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    #2  
Old 03-14-2013
pamu pamu is offline
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Quote:
Originally Posted by amazigh42 View Post
Hello,

How can i put a function into a condition ?
g1 is my function
I tested this in vain


Code:
if [ g1 $1 $2 $3 -ne 0 ];then


Code:
if [ $(g1 $1 $2 $3) -ne 0 ];then

Thanks for yours suggestions
I think function's in bash doesn't accept any variables.

So it should better to define those values before you call your function.

sth like..


Code:
function g1 () {
    echo $((a+b+c))
 }
 
 a=3
 b=4
 c=5
 
 if [ $(g1) -ne 0 ];then
 g1  #do what you want to do..
 fi

Regards,

pamu
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    #3  
Old 03-14-2013
amazigh42 amazigh42 is offline
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Thanks pamu for your help
Whatever i want, if there is a bad parameter in the input file, the function f1 should not process the line with a bad parameter.
I put your suggestion in red but i have this return code.


Code:
line 58: -ne: command not found
line 58: [: missing `]'

I notify this line in green in the script.


Code:
cat file
2013-03-31 09 23
2013-03-31 09 23
#2013-03-31 09 32


Code:
./myscript file


Code:
#!/bin/sh
#########################################################################
DATE=$1
HOUR=$2
MN=$3
function g1 () {
  EC=0
  case "$1" in

    ([1-9][0-9][0-9][0-9]-0[1-9]-0[1-9] | [1-9][0-9][0-9][0-9]-0[1-9]-1[0-9] | [1-9][0-9][0-9][0-9]-0[1-9]-2[0-9] | [1-9][0-9][0-9][0-9]-0[1-9]-3[0-1] | [1-9][0-9][0-9][0-9]-1[0-2]-0[1-9] | [1-9][0-9][0-9][0-9]-1[0-2]-1[0-9] | [1-9][0-9][0-9][0-9]-1[0-2]-2[0-9] | [1-9][0-9][0-9][0-9]-1[0-2]-3[0-1])
# nothing, OK !
    ;;
    (*)
      echo 'Fatal, $1 = '"'$1'"', Date not conform OR absent' >&2
      EC=1
    ;;
  esac

   case "$2" in
     ([01][0-9] | 2[0-3])
        # nothing, OK !
    ;;
    (*)
      echo 'Fatal, $2 = '"'$2'"', Hour in 2 digits between 00 and 23' >&2
      EC=1
    ;;
   esac

   case "$3" in

    ([01][0-9] | [2-5][0-9])
      # nothing, OK !
     ;;
    (*)
      echo 'Fatal, $3 = '"'$3'"', Minute in two digits between 00 and 59' >&2
      EC=1
    ;;
   esac
   [ "$EC" = 1 ]
}

f1() {
echo -e "$DATE $HOUR $MIN"
}

case $# in
        0)      echo -e "# comment1\n# comment2" > list_file
                read -p "Please fill in this list_file: "

                echo $REPLY
                ;;
        1)     if [ ! -f "$1" ]
               then  > $1 && echo -e "# comment1\n# comment1" > $1
                        read -p "Please fill in "$1": "

                        echo $REPLY
               else
                        if [ -f "$1" -a $(grep -v '^#' "$1" | wc -l ) -ne 0 | $(g1 $arg1 $arg2 $arg3) -ne 0 ] # line 58
                        then
                                grep -v '^#' "$1" |
                                                while read arg1 arg2 arg3
                                                do f1 $arg1 $arg2 $arg3
                                                done
                         else
                                        echo "Errors found in date/time - exiting now" >&2
                                        exit 1
                          fi
                                read -p "Please fill in "$1": "
                                echo $REPLY
                fi
               ;;

        3)      echo -e "# Fill in the 3 variables below\n# DATE HOUR MN" > $1
                echo $2 $3 $4 >> "$1"                  # concatenation of variables in $ 1
                                grep -v '^#' "$1" | # Omits the comments
                                while read arg1 arg2 arg3 # Parse the parameters
                                do f1 $arg1 $arg2 $arg3 # Processing parameters for the function f1
                                done
                ;;
 *)      echo "error msg"; exit
esac

    #4  
Old 03-14-2013
Corona688 Corona688 is online now Forum Staff  
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Quote:
Originally Posted by pamu View Post
I think function's in bash doesn't accept any variables.
Incorrect, they take parameters just fine.

You call them directly, outside [ ], like you would an external program.


Code:
if g1 $1 $2 $3
then
...
else
...
fi

And your function should use return to give an integer value that if can use in this manner. It's like exit but only quits a function or sourced script instead of the entire program. Zero means success, nonzero means failure, just like the exit status of an external utility. Your EC variable trick works but such indirectness isn't necessary.


Code:
g1 () {
        if [ something ]
        then
                echo "success"
                return 0
        else
                echo "failure"
                return 1
        fi
}

The Following User Says Thank You to Corona688 For This Useful Post:
pamu (03-15-2013)
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    #5  
Old 03-16-2013
amazigh42 amazigh42 is offline
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Thank you Corona688
I follow yours instructions.

I put an error in the first line (13 for the month)

Code:
cat inputfile
2013-13-31 12 05
2012-12-01 05 24
2011-02-21 09 15

When i launch the script, there are malfunctions.
1) Each line with right or wrong paramaters are printed twice.
I would like the line that has an error is not edited.
It should only return the error code.
And others to be edited once.


Can you correct this script ?
Thank you in advance.


Code:
./my_script inputfile
Fatal, $1 = '2013-13-31', Date not conform OR absent
Errors found in date/time - exiting now
2013-13-31 12 05 line 1
2012-12-01 05 24 line 2
2011-02-21 09 15 line 3
2013-13-31 12 05 line 1
2012-12-01 05 24 line 2
2011-02-21 09 15 line 3


Code:
#!/bin/sh
#########################################################################
g1() {
case "$1" in
([1-9][0-9][0-9][0-9]-0[1-9]-0[1-9] | [1-9][0-9][0-9][0-9]-0[1-9]-1[0-9]  | [1-9][0-9][0-9][0-9]-0[1-9]-2[0-9] |  [1-9][0-9][0-9][0-9]-0[1-9]-3[0-1] | [1-9][0-9][0-9][0-9]-1[0-2]-0[1-9] |  [1-9][0-9][0-9][0-9]-1[0-2]-1[0-9] | [1-9][0-9][0-9][0-9]-1[0-2]-2[0-9]  | [1-9][0-9][0-9][0-9]-1[0-2]-3[0-1])
# RAS, OK !
return 0;
  ;;
(*)
  echo 'Fatal, $1 = '"'$1'"', Date not conform OR absent' >&2
;;
esac
return 1

case "$2" in
([01][0-9] | 2[0-3])
  # nothing, OK !
return 0;
  ;;
(*)
  echo 'Fatal, $2 = '"'$2'"', Hour 2 digits between 00 and 23' >&2
  ;;
esac
return 1

case "$3" in
([01][0-9] | [2-5][0-9])
  # nothing, OK !
return 0;
  ;;
(*)
  echo 'Fatal, $3 = '"'$3'"', Minute in two digits between 00 and 59' >&2
esac
return 1
}

f1() {
echo $1 $2 $3 "line" $4
#[ $1 = $1 ]
}
case $# in
        0)      echo -e "# comment\n# commentaire2" > list_file
                read -p "Please fill in this list_file: "

                echo $REPLY
                ;;
        1)     if [ ! -f "$1" ]
               then  > $1 && echo -e "# comment\n# comment" > $1
                        read -p "Please fill in "$1": "
                        echo $REPLY
               else
                        if [ -f "$1" -a $(grep -v '^#' "$1" | wc -l ) -ne 0 ]
                        then
                                grep -v '^#' "$1" |
                                while read arg1 arg2 arg3
                                do
                                if ! g1 $arg1 $arg2 $arg3
                                 then
                                        echo "Errors found in date/time - exiting now" >&2
                                        #exit 1
                                else

                                        grep -v '^#' "$1" |
                                                while read arg1 arg2 arg3
                                                do f1 $arg1 $arg2 $arg3 $((++line))
                                                done
                                 fi
                                done
                        else
                                read -p "Please fill in "$1": "
                                echo $REPLY
                        fi
                fi
               ;;
  *)      echo "error msg"; exit
esac

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    #6  
Old 03-17-2013
Corona688 Corona688 is online now Forum Staff  
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Do not PM people to bring them back faster. PMing people for technical support is against the rules.

That program is so big and messy I can't tell what you're trying to do, let alone what's wrong with it. Suspect there's a far simpler way to do what you want, whatever it is. Please explain its purpose.
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    #7  
Old 03-18-2013
amazigh42 amazigh42 is offline
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Code:
f1() {
echo $1 $2 $3 "line" $4

Here f1 is a simple function to test the function g1.
g1 is a function which tests the parameters format of an input file.
Theses parameters are YEAR BEGIN_hour END_hour.
Month must be between 1 and 12
Day must be between 1 and 31
Hour must be between 00 and 23 (2 digits)
Minutes must be between 00 and 59 (2 digits)

case 0)
If the script is launched without argument, an inputfile named list_file will be created with comments.
The main engine ie case 1)
If the inputfile exists, the script tests if there are parameters.
Then it parses each parameters to check the validity of the format

When i launch the script, there are malfunctions.
1) Each line with right or wrong parameters are printed twice.
I would like the line that has an error is not printed. It should only return the error code.
And others to be edited once.

I hope to be clearer.

Have a nice day.


Code:
case $# in
        0)      echo -e "# comment1\n# comment2" > list_file
                read -p "Please fill in this list_file: "

                echo $REPLY
                ;;
        1)     if [ ! -f "$1" ]
               then  > $1 && echo -e "# comment1\n# comment1" > $1
                        read -p "Please fill in "$1": "

                        echo $REPLY
               else
                        if [ -f "$1" -a $(grep -v '^#' "$1" | wc -l ) -ne 0 | $(g1 $arg1 $arg2 $arg3) -ne 0 ] # line 58
                        then
                                grep -v '^#' "$1" |
                                                while read arg1 arg2 arg3
                                                do f1 $arg1 $arg2 $arg3
                                                done
                         else
                                        echo "Errors found in date/time - exiting now" >&2
                                        exit 1
                          fi
                                read -p "Please fill in "$1": "
                                echo $REPLY
                fi
               ;;

        3)      echo -e "# Fill in the 3 variables below\n# DATE HOUR MN" > $1
                echo $2 $3 $4 >> "$1"                  # concatenation of variables in $ 1
                                grep -v '^#' "$1" | # Omits the comments
                                while read arg1 arg2 arg3 # Parse the parameters
                                do f1 $arg1 $arg2 $arg3 # Processing parameters for the function f1
                                done
                ;;
 *)      echo "error msg"; exit
esac

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