error in trim_copy() was a typo: "ouput" -> "output" (but no segfault)
error in trim_nocopy() was an undeclared variable (that also needs to be initialized. segfault, if the new variable is not initialized and the string contains no nonspace characters)
btw. trim_nocopy() has no real practical reason to exist. It is only to show that a left trimming can be done without writing to the string at all, just by changing the start pointer. Also right trimming can be done by just writing a zero after the last nonspace. In fact the trim_copy() function is the one you should always use, both for in place (input==output) or copying operations. Also it makes sense to switch the parameters, so they are in sync with other c std lib string functions like strcpy() and strcat().
ok, now the fixed version:
Code:
void trim_copy(char *input, char *output)
{
char *end = output;
char c;
// skip spaces at start
while(*input && isspace(*input))
++input;
// copy the rest while remembering the last non-whitespace
while(*input)
{
// copy character
c = *(output++) = *(input++);
// if its not a whitespace, this *could* be the last character
if( !isspace(c) )
end = output;
}
// write the terminating zero after last non-whitespace
*end = 0;
}
void trim_inplace(char *s)
{
trim_copy(s, s);
}
char *trim_nocopy(char *s)
{
char *start = s;
// skip spaces at start
while(*start && isspace(*start))
++start;
char *i = start;
char *end = start;
// iterate over the rest remebering last non-whitespace
while(*i)
{
if( !isspace(*(i++)) )
end = i;
}
// write the terminating zero after last non-whitespace
*end = 0;
return start;
}
Hi ,
I have a code like this:
uid=scott
password=tiger
database=db01
cat >runid_val.sql<<-EOA
SET ECHO OFF
SET FEEDBACK OFF
SET HEADING OFF
SELECT trim(runid_seq.nextval) FROM dual;
EXIT
EOA
echo `cat runid_val.sql`
V_RUNID=`sqlplus -s $uid/$password@$database @runid_val.sql`... (5 Replies)
Hi,
I have a CSV file with footer information as below. The third value is the number of records in the file. Sometimes it contains both leading and trailing white spaces which i want to trim using awk.
C,FOOTER , 00000642
C,FOOTER , 00000707
C, FOOTER,... (2 Replies)
Hi All;
Having a problem with a file..
the file contains the following data... (a snapshot)
1331F9E9DB7C2BB80EAEDE3A8F043B94,AL7 1DZ,M,50
186FDF93E1303DBA217279EC3671EA91,NG5 1JU,M,24
3783FFAF602015056A8CD21104B1AAAF,CH42 4NQ,M,17
It has 3 columns sepreated by a ,
the second column... (7 Replies)
Dear Members,
Suppose i have a variable test which stores a string as below:
test='John drives+++++++++a+++++car'
now i want to use sed on the above variable and replace + with a white space, so that i get
echo $test should give me
'john drives a car'
Between... (1 Reply)
Hi,
What sed command (if sed is the right command) can remove ALL white space from my file. I have a csv, except I want to remove all white space between commas and characters.
My idea (without testing)
sed 's/ //g'
Is there a better way? (18 Replies)
our user creates a text file with a white space on the filename. this same file is transfered to unix via automation tool. i have a korn shell script that reads these files on a input directory and connects to oracle database to run the oracle procedures which will load the data from each of the... (2 Replies)
Hi,
Consider the data (FS = |):
1| England |end
2| New Zealand |end
3|Australia|end
4| Some Made Up Country |end
5| West Indies|end
I want the output to be (i.e. without the leading and trailing white space from $2)
England
New Zealand
Australia
Some Made Up Country
West... (4 Replies)
hi guys
how can i add spacein file name with sed if strings have no space around dash
input
19-20
( 18-19 )
ABC-EFG
output after add white space
19 - 20
(18 - 19 )
ABC - EFG
thx in advance (2 Replies)
Hi Guys,
Hope, you all are doing good out there.
I am writing a shell script and currrint in need of your help.
This is what I need to do;
I have position based plain file. One of the fields is 15 character long. I need to fill that field. The problem is that the value is dynamic, it could... (4 Replies)
In Shell, I have output of a unix command as
test1
test2015
but I want it as
test1 test2015
can anyone help me out.
Use code tags, thanks. (3 Replies)
Discussion started by: OscarS
3 Replies
LEARN ABOUT V7
string
STRING(3) Library Functions Manual STRING(3)NAME
strcat, strncat, strcmp, strncmp, strcpy, strncpy, strlen, index, rindex - string operations
SYNOPSIS
char *strcat(s1, s2)
char *s1, *s2;
char *strncat(s1, s2, n)
char *s1, *s2;
strcmp(s1, s2)
char *s1, *s2;
strncmp(s1, s2, n)
char *s1, *s2;
char *strcpy(s1, s2)
char *s1, *s2;
char *strncpy(s1, s2, n)
char *s1, *s2;
strlen(s)
char *s;
char *index(s, c)
char *s, c;
char *rindex(s, c)
char *s;
DESCRIPTION
These functions operate on null-terminated strings. They do not check for overflow of any receiving string.
Strcat appends a copy of string s2 to the end of string s1. Strncat copies at most n characters. Both return a pointer to the null-termi-
nated result.
Strcmp compares its arguments and returns an integer greater than, equal to, or less than 0, according as s1 is lexicographically greater
than, equal to, or less than s2. Strncmp makes the same comparison but looks at at most n characters.
Strcpy copies string s2 to s1, stopping after the null character has been moved. Strncpy copies exactly n characters, truncating or null-
padding s2; the target may not be null-terminated if the length of s2 is n or more. Both return s1.
Strlen returns the number of non-null characters in s.
Index (rindex) returns a pointer to the first (last) occurrence of character c in string s, or zero if c does not occur in the string.
BUGS
Strcmp uses native character comparison, which is signed on PDP11's, unsigned on other machines.
STRING(3)